Bio-based polymers from raw lignocellulosic biomass

ABSTRACT

Disclosed herein is a method of making polymerizable bio-based monomers containing one phenolic hydroxyl group which has been derivatized to provide at least one polymerizable functional group which is an ethylenically unsaturated functional group (such as a [meth]acrylate group), where the precursors of the polymerizable bio-based monomers are derived from raw lignin-containing biomass. Also disclosed herein are bio-based copolymers prepared from such bio-based monomers and a co-monomer, and methods of making and using such bio-based copolymers. In particular, the bio-based copolymers can be used as pressure sensitive adhesives, binders, and polymer electrolytes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from United States ProvisionalApplication Nos. 62/615,040, filed Jan. 9, 2018 and 62/713,571 filedAug. 2, 2018; and is a continuation-in-part of U.S. patent applicationSer. No. 15/208,135 filed Jul. 12, 2016, which claims priority from U.S.Provisional Application No. 62/191,551, filed Jul. 13, 2015. Thedisclosures of the aforementioned applications are incorporated hereinby reference in their entirety for all purposes.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

This invention was made with government support under Grant Nos.DE-SC0014458 and DE-SC0001004 awarded by the Department of Energy andGrant No. CHE-1507010 awarded by the National Science Foundation. Thegovernment has certain rights in the invention.

FIELD OF THE INVENTION

The present invention relates to polymerizable bio-based monomerscontaining one phenolic hydroxyl group, which has been derivatized toprovide at least one polymerizable functional group, which is anethylenically unsaturated functional group, derived from rawlignin-containing biomass, bio-based copolymers prepared from suchbio-based monomers and a co-monomer, and methods of making and usingsuch bio-based copolymers. In particular, the present inventions relateto pressure sensitive adhesives, binders, and polymer electrolytescomprising the bio-based copolymers.

DESCRIPTION OF THE RELATED ART

To address sustainability challenges associated with petrochemicals,researchers have exploited a plethora of renewable chemicals to generatebio-based, cost-effective, and thermomechanically useful macromolecules.Lignin is one renewable resource that shows promise as a desirablealternative to petroleum feedstocks, largely due to its abundance as abyproduct of pulp and paper processing and biorefining. Correspondinglignin-based bio-oils (e.g., the volatile fraction of pyrolyzed ligninor the soluble fraction of depolymerized lignin) contain numerousaromatic compounds that structurally resemble common monomers (e.g.,bisphenol A and styrene) for various polymer applications. The aromaticmoieties in lignin are linked by several types of robust C═C and C—Obonds, and deconstruction of lignin therefore generates mixtures ofdisparate compounds (monophenols, dimers, and oligomers).^(4,10-14) Theexact structure and composition of a lignin-based bio-oil is highlyvariable, depending on the biomass resource, lignin type, anddepolymerization route, among other factors. In general, the nativecomponents of all lignin-based bio-oils include phenols and guaiacols(2-methoxyphenols), whereas the native components of angiosperm(hardwood, e.g., oak and maple trees) and graminaceous (grassy, e.g.,switchgrass and corn stover) bio-oils also include syringols(2,6-dimethoxyphenols).

Although bio-based model compounds, and in particular lignin modelcompounds have been extensively explored toward the formulation of newproducts for applications, such as thermoplastics, thermoplasticelastomers, coatings, pressure sensitive adhesives (PSAs), composites,and resins,¹⁷⁻²⁶ a major unanswered question remains—if these bio-basedcompounds can be harvested from raw biomass to produce designermaterials in a scalable and cost-effective manner. Essentially, asignificant gap exists between deriving well-defined chemicals from rawbiomass and directly utilizing these chemicals for the formulation ofspecialized consumer products.

Hence, there is a need for a robust and scalable process fordepolymerization, purification, functionalization, and polymerization,along with potential recycle and reuse of catalyst and solvents in theprocess, which are essential to reduce the energy and cost associatedwith ‘green’ materials fabrication and to encourage the sustained use ofbiomass-derived materials in mainstream applications.

BRIEF SUMMARY OF THE INVENTION

The present invention discloses a process for harnessing high purityaromatic compounds in high yield directly from the depolymerization ofraw biomass for the preparation of advanced and high performancepolymers for applications such as pressure sensitive adhesives (PSAs)and binders and electrolytes for lithium-ion batteries.

Various exemplary aspects of the present invention may be summarized asfollows:

In an aspect, there is provided a method for producing a bio-basedcopolymer using bio-based monomers obtained from biomass material,wherein the method comprises:

-   -   a) contacting a biomass with a hydrogenolysis catalyst in the        presence of hydrogen at a first temperature, thereby        hydrogenolyzing the biomass to produce a mixture of        depolymerized lignin products and residual feedstock components,        wherein at least one of the mixture of depolymerized lignin        products contains a phenolic hydroxyl group and has a structure        corresponding to formula (I):

-   -    wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl,        propylene, formyl, a propanoate salt, a propanoate ester, an        acetate salt, or an acetate ester (such as methyl acetate), and        wherein R₃ and R₄ are independently selected from hydrogen or        methoxy;    -   b) separating the mixture of depolymerized lignin products in a        liquid stream from the residual feedstock components;    -   c) extracting at least one depolymerized lignin product        containing a phenolic hydroxyl group from the liquid stream of        the depolymerized lignin products, wherein optionally solvent is        removed from the liquid stream before the extracting;    -   d) reacting the at least one extracted depolymerized lignin        product containing a phenolic hydroxyl group with a        functionalized reagent containing at least one functional group        reactive with the phenolic hydroxyl group, thereby forming one        or more bio-based monomers having a structure corresponding to        formula (II):

-   -    wherein R₂ is the substituent comprised of at least one        polymerizable functional group which is an ethylenically        unsaturated functional group; and    -   e) forming a copolymer.

In an embodiment of the method, the hydrogenolysis catalyst comprises acatalyst comprising:

a. at least one of Ru, Ni, Pd, NiPd, NiRu, and RuPd supported on asupport selected from the group consisting of carbon, alumina, silica,and alumina-silica,

-   -   b. a metal sulfide selected from the group consisting of CoS₂,        CoS, MoS₂, WS₂, and mixtures thereof, or    -   c. a mixture thereof.

In another embodiment of the method, the functionalized reagent isselected from the group consisting of anhydrides, acyl halides,carboxylic acids, acrylamides, epoxies, and vinyls.

In yet another embodiment of the method, the functionalized reagent is[meth]acrylic anhydride, [meth]acrylic acid, or [meth]acryloyl chloride,and wherein the one or more polymerizable bio-based monomers comprises:

-   -   (i) a phenol [meth]acrylate selected from the group consisting        of cresol [meth]acrylate, 4-ethylphenol [meth]acrylate,        4-propylphenol [meth]acrylate, 4-hydroxybenzaldehyde        [meth]acrylate, and 3-(4-hydroxyphenol)propanoate        [meth]acrylate;    -   (ii) a monomethoxyphenol [meth]acrylate selected from the group        consisting of guaiacol (monomethoxy-substituted phenol)        [meth]acrylate, 4-ethylguaiacol [meth]acrylate, creosol        [meth]acrylate, 4-propylguaiacol [meth]acrylate, vanillin        [meth]acrylate, and methyl homovanillate [meth]acrylate (methyl        2-(4-hydroxy-3-methoxyphenyl)acetate [meth]acrylate);    -   (iii) a dimethoxyphenol [meth]acrylate, or syringol        (dimethoxy-substituted phenol) [meth]acrylate); or    -   (iv) combinations thereof.

In an aspect of the method, the step of forming a bio-based copolymercomprises forming a block copolymer comprising at least one bio-basedpolymeric block comprising, in polymerized form, at least one bio-basedmonomer corresponding to formula (II) and a co-monomer-based polymericblock.

In an embodiment of the method, the co-monomer-based polymeric blockcomprises, in polymerized form, at least one of ethylene oxide,propylene oxide, (oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt or comprisesoligo-oxyethylene, oligo-oxypropylene, poly(ethylene oxide) orpoly(propylene oxide).

In another embodiment of the method, the step of forming a blockcopolymer comprises forming a triblock copolymer having a midblock andtwo glassy end blocks, wherein the co-monomer-based polymeric block isthe midblock and is formed by polymerizing a co-monomer comprising analkyl [meth]acrylate, a diene, or an olefin and wherein at least one ofthe two glassy end blocks is formed by polymerizing the at least onebio-based monomer

In yet another aspect of the method, the step of forming a bio-basedcopolymer comprises co-polymerizing at least one bio-based monomercorresponding to formula (II) with one or more co-monomers other thanthe at least one bio-based monomer.

In an embodiment, the one or more co-monomers comprises aco-polymerizable ion-conducting co-monomer, and wherein the copolymer isa random, statistical, graft, star, brush or cyclic copolymer.

In another embodiment, the co-polymerizable ion-conducting co-monomercomprises at least one of (oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt.

In accordance with various embodiments of the method, the biomass is atleast one of lignocellulose biomass, solid wood waste, forest woodwaste, lignin rich food waste, energy crops, animal waste, agriculturalwaste, or lignin residue generated by cellulosic biorefinery or paperpulping industries.

In an aspect, there is provided a bio-based copolymer comprising inpolymerized form:

-   -   (i) at least one polymerizable lignin-based monomer having a        structure corresponding to formula (II):

-   -    wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl,        propylene, formyl, propanoate salt, a propanoate ester, an        acetate salt, or an acetate ester (e.g., methyl acetate),    -    wherein R₂ is a substituent comprised of at least one        polymerizable functional group which is an ethylenically        unsaturated functional group, and wherein R₃ and R₄ are        independently selected from hydrogen or methoxy; and    -   (ii) at least one ion-conducting co-monomer other than the        bio-based monomer.

In an embodiment of the bio-based copolymer, the bio-based copolymer isa block copolymer comprising at least one bio-based polymeric blockcomprising, in polymerized form, at least one bio-based monomercorresponding to formula (II) and an ion-conducting co-monomer-basedpolymeric block.

In another embodiment, the ion-conducting co-monomer-based polymericblock comprises, in polymerized form, at least one of ethylene oxide,propylene oxide, (oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt or comprisesat least one of oligo-oxyethylene, oligo-oxypropylene, poly(ethyleneoxide), or poly(propylene oxide).

In one embodiment, the co-monomer-based polymeric block comprises apoly((oligo-oxyethylene) [meth]acrylate) block, and wherein thebio-based copolymer is a diblock bio-based copolymer having thefollowing structure (III) or a triblock having the following structure(IV):

-   -   wherein x is in the range of 2-1000; n is in the range of        10-500; m is in the range of 10-1000; R₁ is hydrogen, methyl,        ethyl, n-propyl, i-propyl, propylene, formyl, a propanoate salt,        a propanoate ester, an acetate salt, or an acetate ester (e.g.,        methyl acetate); and R₃ and R₄ are independently selected from        hydrogen or methoxy.

In an embodiment, the at least one ion-conducting co-monomer is aco-polymerizable co-monomer comprising at least one of(oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt, and whereinthe copolymer is a random, statistical, graft, star, brush, or cycliccopolymer.

In an aspect, there is provided a binder for a battery comprising thebio-based copolymer, as disclosed hereinabove.

In another aspect, there is provided an electrode comprising the binder,as disclosed hereinabove and an electrode active material.

In an embodiment of the electrode, the polymer electrolyte comprises thebio-based copolymer of the present invention and at least one salt.

In another embodiment, the at least one salt comprises at least onelithium salt selected from the group consisting of LiBr, LiCl, LiClO₄,LiPF₆, LiAsF₆, LiSbF₆, LiBF₄, LiCF₃SO₃, LiN(FSO₂)₂, LiN(CF₃SO₂)₂,LiN(C₂F₅SO₂)₂, LiC₆F₃N₄, LiC(CF₃SO₂)₃, Li₂B₁₀Cl₁₀, LiB(OCH₃)₄,LIB(C₂O₄)₂, LiB(CN)₄, LiBC₂O₄F₂, LiB(C₃O₄F)₂, lithium acetate, andLiAlCl₄.

In another aspect, there is provided an electrochemical devicecomprising an electrode in electrical contact with a polymerelectrolyte, wherein at least one of the electrode and the polymerelectrolyte comprises the bio-based copolymer of the present invention.

In an aspect, there is provided an article comprising an adhesivecomposition disposed over a substrate, wherein the adhesive compositioncomprises a bio-based block copolymer comprising:

-   -   (i) at least one bio-based polymeric block comprising, in        polymerized form, at least one polymerizable bio-based monomer        having a structure corresponding to formula (II):

-   -   -   wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl,            propylene, formyl, a propanoate salt ester, a propanoate            ester, an acetate salt, or an acetate ester (e.g., methyl            acetate),        -   wherein R₂ is a substituent comprised of at least one            polymerizable functional group that is an ethylenically            unsaturated functional group,        -   wherein R₃ and R₄ are independently selected from hydrogen            or methoxy, and wherein the ethylenically unsaturated            functional group has been polymerized in the at least one            bio-based polymeric block; and

    -   (ii) a co-monomer-based polymeric block comprising, in        polymerized form, at least one co-monomer other than the at        least one bio-based monomers, wherein the at least one        co-monomer comprises an alkyl [meth]acrylate, a diene, or an        olefin.

In an embodiment of the article, the at least one co-monomer comprisesan alkyl [meth]acrylate containing an alkyl group selected from thegroup consisting of C1 to C18 alkyl groups.

In another embodiment, the block polymer is a bio-based triblockcopolymer, having a midblock and two glassy end blocks, wherein themidblock is comprised of the alkyl [meth] acrylate in polymerized formand one or both of the glassy end blocks is or are comprised of the atleast one bio-based monomer in polymerized form.

In yet another embodiment, R₁ is propyl and R₃ and R₄ are methoxy; andthe triblock bio-based copolymer is poly(4-propylsyringylacrylate-b-butyl acrylate-b-4-propylsyringyl acrylate) having thefollowing structure (V):

and

-   -   wherein n is in the range of 20-100; and m is in the range of        50-1000.    -   In one embodiment of the article, the adhesive composition is a        pressure sensitive adhesive composition.    -   In another embodiment, the article further comprises one or more        additives selected from the group consisting of tackifiers,        plasticizers, viscosity modifiers, photoluminescent agent,        anti-counterfeit and UV-reactive additives, dyes/pigments,        anti-static materials, surfactants, and lubricants.    -   In another embodiment of the article, the substrate comprises a        polymeric film, a paper label, a tape backing, a graphic        article, a plastic article, a metal article, a wound dressing, a        protection film or tape, or a release liner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a general process of forming a bio-based copolymer from rawbiomass (4-propylsyringol: R=OCH₃; 4-propylguaiacol: R═H).

FIG. 2A shows gas chromatography (GC) trace of raw biomassdepolymerization products before extraction with cyclohexane.

FIG. 2B shows gas chromatography (GC) trace of raw biomassdepolymerization products after extraction with cyclohexane.

FIG. 3 shows ¹H NMR spectrum of SaBSa in chloroform-d (with TMS as aninternal standard).

FIG. 4 shows size exclusion chromatography (SEC) traces of poly(butylacrylate) (PBA) (solid line, M_(n)=49.7 kg mol⁻¹, Ð=1.11) andpoly(4-propylsyringyl acrylate-b-butyl acrylate-b-4-propylsyringylacrylate) (SaBSa) (dashed line, M_(n)=66.4 kg mol⁻¹, Ð=1.15). RI denotesrefractive index detector response.

FIG. 5 shows differential scanning calorimetry (DSC) traces of thesecond heating (exotherm up, heating rate=5° C. min⁻¹ under continuousN₂ flow at 50 mL mi⁻¹) for SaBSa [solid line, M_(n)=66.4 kg mol⁻¹, 22 wt% P4pSA] and poly(methyl methacrylate-b-butyl acrylate-b-methylmethacrylate) (MBM) [dashed line, M_(n)=66.9 kg mol⁻¹, 23 wt %poly(methyl methacrylate) (PMMA)].

FIGS. 6A-6D show a) 2D small angle X-ray scattering (SAXS) pattern andb) azimuthally-integrated 1D SAXS data for SaBSa [principal scatteringpeak, q*, at 0.030 Å⁻¹ (arrow), corresponding to a domain spacing(d*=2n/q*) of ˜21 nm]; c) 2D SAXS pattern and d) azimuthally-integrated1D SAXS data for MBM [q*=0.031 Å⁻¹ (arrow), corresponding to a domainspacing of ˜20 nm].

FIG. 7 shows a) mass remaining as a function of temperature for SaBSa(solid line, M_(n)=66.4 kg mol⁻¹, 22 wt % P4pSA) and MBM (dash-dottedline, M_(n)=66.9 kg mol⁻¹, 23 wt % PMMA); b) the first derivative ofmass remaining curve a) as a function of temperature for SaBSa (dashedline, M_(n)=66.4 kg mol⁻¹, 22 wt % P4pSA) and MBM (dotted line,M_(n)=66.9 kg mol⁻¹, 23 wt % PMMA). The heating rate was 10° C. min⁻¹under air flow.

FIG. 8 shows gel permeation chromatography (GPC) trace of PGM.

FIG. 9 shows thermal transitions in PGM-b-POEM as determined from DSC.Third heating trace is reported.

FIG. 10 shows conductivity (alternating current impedance spectroscopy)as a function of temperature of PGM-b-POEM (squares) and PS-b-POEM(diamonds).

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION

As used herein, the term “bio-based monomer” refers to a chemicalcompound containing one phenolic hydroxyl group that has beenderivatized to provide at least one polymerizable functional group,which is an ethylenically unsaturated functional group, and which isderived from lignin-containing biomass, including, but not limited to,softwoods, lignocellulose biomass, solid wood waste, forest wood waste,lignin rich food waste, energy crops, animal waste, agricultural waste,or lignin residue generated by cellulosic biorefinery or paper pulpingindustries. Suitable lignin-rich food wastes include, but are notlimited to nutshells, olive seeds, and tomato peels and seeds. Suitableenergy crops include but are not limited to wheat, corn, soybean,sugarcane, arundo, camelina, carinate, jatropha, miscanthus, sorghum,and switchgrass.

Suitable polymerizable bio-based monomers of the present inventioninclude, but are not limited to:

-   -   (i) an unsubstituted phenol [meth]acrylate or a substituted        phenol [meth]acrylate, such as cresol [meth]acrylate,        4-ethylphenol [meth]acrylate, 4-propylphenol [meth]acrylate,        4-hydroxybenzaldehyde [meth]acrylate, or        3-(4-hydroxyphenol)propanoate [meth]acrylate,    -   (ii) a monomethoxyphenol [meth]acrylate, such as guaiacol        (monomethoxy-substituted phenol) [meth]acrylate, 4-ethylguaiacol        [meth]acrylate, creosol [meth]acrylate, 4-propylguaiacol        [meth]acrylate, vanillin [meth]acrylate, or methyl homovanillate        [meth]acrylate (methyl 2-(4-hydroxy-3-methoxyphenyl)acetate        [meth]acrylate),    -   (iii) a dimethoxyphenol [meth]acrylate, such as a syringol        [meth]acrylate, or    -   (iv) combinations thereof.

As used herein, the terms “syringols” and “guaiacols” refer to phenoliccompounds derived from depolymerized lignins containing one phenolichydroxyl group and in addition two methoxy groups and one methoxy grouprespectively. Syringols, guaiacols, and phenols can be obtained from anysuitable lignin-containing biomass, including, but not limited to,softwoods, lignocellulose biomass, solid wood waste, forest wood waste,lignin rich food waste, energy crops, animal waste, agricultural waste,or lignin residue generated by cellulosic biorefinery or paper pulpingindustries. Suitable examples of lignin-containing biomass include, forexample and without limitation, oak, alder, chestnut, ash, aspen, balsa,beech, birch, boxwood, walnut, laurel, camphor, chestnut, cherry,dogwood, elm, eucalyptus, pear, hickory, ironwood, maple, olive, poplar,sassafras, rosewood, bamboo, coconut, locust, and willow trees, as wellas, but not limited to, grasses (e.g., switchgrass, bamboo, straw),cereal crops (e.g., barley, millet, wheat), agricultural residues (e.g.,corn stover, bagasse), and lignin-rich food wastes (e.g., nutshells,olive seeds, and tomato peels and seeds). Syringol, guaiacol, and phenolmolecules can also come from petrochemical resources.

As used herein, the term “syringol” refers to a 2,6-dimethoxyphenol andthe term “guaiacol” refers to a 2-methoxyphenol, with different moieties(including hydrogen) as substituents in the 4-position of the aromaticring. A syringol and guaiacol thus corresponds to compounds having thefollowing structures respectively:

The p-position moiety (R₁) may be, for example, hydrogen (—H); alkylgroups (including linear, branched and cyclic alkyl groups, includingC1-C3 alkyl groups (such as methyl, ethyl, n-propyl, and i-propyl),alkylene groups (such as propylene), formyl, propanoate (in salt orester form), or acetate (in salt or ester form). Any of these moietiesmay be attached as substituents to the aromatic rings of other phenolswithin the scope of the present invention.

Method of Producing a Bio-Based Copolymer Using Lignin-Based Monomers

In an aspect of the invention, there is provided a method for producinga bio-based copolymer of the present invention, as disclosedhereinbelow, using bio-based monomers obtained from biomass material.The method may include a first step of contacting a biomass with ahydrogenolysis catalyst in the presence of hydrogen at a firsttemperature, thereby hydrogenolyzing the biomass to produce a mixture ofdepolymerized lignin products and residual feedstock components, whereinat least one depolymerized lignin product in the mixture ofdepolymerized lignin products contains one phenolic hydroxyl group andhas a structure corresponding to formula (I):

wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl, propylene,formyl, a propanoate salt, a propanoate ester, an acetate salt, or anacetate ester (e.g., methyl acetate), and R₃ and R₄ are independentlyselected from hydrogen or methoxy.

In one embodiment, both R₃ and R₄ are hydrogen and the resultingdepolymerized lignin product is a bio-derived phenol. In anotherembodiment, R₃ is hydrogen, and R₄ is methoxy group and the resultingdepolymerized lignin product is a bio-derived the guaiacol. In anotherembodiment, both R₃ and R₄ are methoxy groups and the resultingdepolymerized lignin product is a bio-derived syringol. In anembodiment, the mixture of depolymerized lignin products comprises amixture of a bio-derived phenol, a bio-derived guaiacol and abio-derived syringol.

Any suitable hydrogenolysis catalyst may be used, including, but notlimited to a catalyst comprising:

-   -   a. at least one of Ru, Ni, Pd, NiPd, NiRu, or RuPd supported on        at least one support selected from the group consisting of        carbon, alumina, silica, and alumina-silica,    -   b. a metal sulfide selected from the group consisting of CoS₂,        CoS, MoS₂, WS₂, or a mixture thereof, or    -   c. a mixture thereof.

The method further comprises separating the mixture of depolymerizedlignin products in a liquid stream from the residual feedstockcomponents and extracting at least one depolymerized lignin productcontaining one phenolic hydroxyl group from the liquid stream of thedepolymerized lignin products. In an embodiment, the depolymerizedlignin products in a liquid stream may be separated by filtration fromthe residual feedstock components. Furthermore, the solvent in theliquid stream may be removed by any suitable method such asdistillation, and the solid residue containing depolymerized ligninproducts may be contacted with at least one non-polar organic solvent,in particular a hydrocarbon solvent (e.g., an aliphatic hydrocarbonsolvent such as cyclohexane or hexane) to extract the depolymerizedlignin products containing one phenolic hydroxyl group.

The method further comprises reacting the at least one extracteddepolymerized lignin product containing one phenolic hydroxyl group witha functionalized reagent containing at least one functional groupreactive with the phenolic hydroxyl group, thereby forming one or morepolymerizable bio-based monomers having a structure corresponding toformula (II):

wherein R₂ is the substituent comprised of at least one polymerizablefunctional group, which is an ethylenically unsaturated functionalgroup.

A “polymerizable bio-based monomer” in the context of the presentinvention is a bio-based monomer that has been modified to incorporate amoiety containing at least one polymerizable functionality (other than ahydroxyl group) at the phenol (—OH) position. The polymerizablefunctionality, in certain embodiments of the invention, is polymerizablethrough chain-growth polymerization mechanisms, such as free-radical andcontrolled-radical polymerization. In other embodiments, however, thepolymerizable functionality is polymerizable through other mechanisms,such as anionic polymerization, cationic polymerization, condensationpolymerization, ring-opening polymerization and so forth.

Polymerizable functionalities (e.g., for R₂) include, but are notlimited to, ethylenically unsaturated functionalities such asmethacrylate, acrylate, maleinate, maleate, fumarate, acrylamide,methacrylamide, vinyl, allyl, vinyl ester, and vinyl amide groups. Thesepolymerizable groups can be attached to the bio-based precursors usingacylation or esterification reactions between the phenol (aromatichydroxyl group) and a reactive moiety (i.e., a moiety reactive with thephenol) bearing at least one polymerizable group (e.g., R₂). Reagentsthat can provide the new polymerizable group include, but are notlimited to, anhydrides (e.g., methacrylic anhydride, acrylic anhydride,maleic anhydride), acyl halides (e.g., methacryloyl chloride, acryloylchloride, fumaryl chloride).

The term [meth]acrylate or [meth]acrylamide, as used herein, means themonomer can be either an acrylate or methacrylate (in the case of a[meth]acrylate) or acrylamide or methacrylamide (in the case of a[meth]acrylamide). Preferred co-monomers, in certain embodiments of theinvention, include those capable of providing bio-based copolymers whichare glassy materials at room temperature (e.g., styrene and methyl[meth]acrylate) and/or other monomers that can be derived from lignin orother biomass materials (e.g., vanillin [meth]acrylate and otherguaiacol [meth]acrylates). In one embodiment of the invention, abio-based monomer (e.g., a phenol-based monomer, a guaiacol-basedmonomer, or a syringol-based monomer) is prepared by a method comprisingreacting the depolymerized lignin product (e.g., a phenol, a guaiacol,or a syringol) containing one phenolic hydroxyl group with afunctionalized reagent containing at least one polymerizable functionalgroup other than a hydroxyl group (in particular, a polymerizablefunctional group which is an ethylenically unsaturated functional group,such as for example —CH═CH₂, —C(═O)—CH═CH₂, or —C(═O)—C(CH₃)═CH₂) and atleast one functional group reactive with the phenolic hydroxyl group.For example, the functionalized reagent may be selected from the groupconsisting of anhydrides, acyl halides, carboxylic acids, acrylamides,epoxies, and vinyls. The polymerizable functional group may be selectedfrom any of the above-mentioned polymerizable functionalities,particularly free radical-polymerizable functional groups, e.g.,ethylenically unsaturated groups such as [meth]acrylates and vinylgroups. The functional group reactive with the phenolic hydroxyl groupmay be selected, for example, from the group consisting of anhydridegroups, acyl halide groups, epoxy groups, carboxylic acid groups, estergroups, vinyl halide groups and the like. Methacrylic anhydride, acrylicanhydride, and maleic anhydride are examples of particularly preferredfunctionalized reagents. A catalyst may be present to promote thedesired reaction between the phenolic hydroxyl group and the functionalgroup reactive with the phenolic hydroxyl group. For example, when thefunctionalized reagent is an anhydride, a tertiary amine may be utilizedas a catalyst, typically at a concentration of from about 0.01 to about0.1 mol/mol tertiary amine/anhydride. It may be advantageous to reactthe anhydride and the depolymerized lignin product containing onephenolic hydroxyl group (e.g., a phenol, a guaiacol, or a syringol) atan approximately 1:1 molar ratio or with the anhydride in a slight molarexcess relative to the depolymerized lignin product containing onephenolic hydroxyl group. For example, the molar ratio ofanhydride:depolymerized lignin product containing one phenolic hydroxylgroup can be from about 1:1 to about 1.2:1. An inhibitor may be presentduring reaction of the depolymerized lignin product and thefunctionalized reagent, to stabilize the bio-based monomer therebyformed and to reduce the extent of degradation or byproduct formation.Suitable inhibitors include, but are not limited to, sterically hinderedalkylated phenols such as t-butyl-substituted phenols; typically, itwill be desirable for about 500 ppm to about 3000 ppm of inhibitor to bepresent, based on the weight of the functionalized reagent. The reactionof the depolymerized lignin product containing one phenolic hydroxylgroup and functionalized reagent may be carried out in bulk or in aninert organic solvent such as toluene or tetrahydrofuran. The reactiontemperature may be from about room temperature (about 25° C.) to about100° C., for example. The reaction between the depolymerized ligninproduct and the functionalized reagent is allowed to proceed at thedesired temperature for a time effective to achieve the desired degreeof conversion of the starting materials to the bio-based monomer(typically, about 1 hour to about 100 hours). The reaction product,containing the bio-based monomer, thereby obtained may then be worked upand purified using any of the techniques known in the field of organicchemistry, including washing a solution of the reaction product in awater immiscible organic solvent with one or more volumes of water(which may be neutral, acidic and/or basic), neutralization,concentration (removal of solvent, by distillation for example),fractionation, precipitation, (re)crystallization, distillation, and/orchromatography and the like. It will generally be advantageous to purifythe bio-based monomer to a molar purity of at least 99% prior toutilizing the bio-based monomer in a polymerization, although lowerpurities can be used if the impurity(ies) do(es) not negatively impactthe desired polymerization.

In one embodiment, the functionalized reagent is [meth]acrylicanhydride, [meth]acrylic acid or [meth]acryloyl chloride, and the one ormore polymerizable bio-based monomers comprises:

-   -   (i) a phenol [meth]acrylate selected from the group consisting        of cresol [meth]acrylate, 4-ethylphenol [meth]acrylate,        4-propylphenol [meth]acrylate, 4-hydroxybenzaldehyde        [meth]acrylate, and 3-(4-hydroxyphenol)propanoate        [meth]acrylate;    -   (ii) a monomethoxyphenol [meth]acrylate selected from the group        consisting of guaiacol (monomethoxy-substituted phenol)        [meth]acrylate, 4-ethylguaiacol [meth]acrylate, creosol        [meth]acrylate, 4-propylguaiacol [meth]acrylate, vanillin        [meth]acrylate, and methyl homovanillate [meth]acrylate (Methyl        2-(4-hydroxy-3-methoxyphenyl)acetate [meth]acrylate);    -   (iii) a dimethoxyphenol [meth]acrylate, or syringol        (dimethoxy-substituted phenol) [meth]acrylate); or    -   (iv) combinations thereof.

In accordance with various embodiments of the present invention, themethod also comprises forming a bio-based copolymer. As used herein, theterm “bio-based copolymer” refers to an oligomeric or macromolecularmolecule comprised of at least one bio-based monomer unit that has beenpolymerized at least by reaction of the polymerizable functionalgroup(s) present in the monomer.

In an embodiment, the step of forming a bio-based copolymer comprisesforming a bio-based block copolymer comprising at least one bio-basedpolymeric block comprising, in polymerized form, at least one bio-basedmonomer corresponding to formula (II) and a co-monomer-based polymericblock.

In another embodiment, the step of forming a bio-based copolymercomprising co-polymerizing at least one bio-based monomer correspondingto formula (II) with one or more co-monomers other than the at least onebio-based monomer

In accordance with the present invention, the forming of a bio-basedcopolymer may further comprise the use of one or more difunctional ormultifunctional co-monomers to make graft, brush-like, and star-likematerials. Bio-based monomers with modified R₁ groups may provide aneven greater range of properties than those accessible through bio-basedmonomers with native R₁ groups.

Bio-based copolymers in accordance with the present invention are notparticularly limited with respect to their molecular weights or theirgeometry. For example, the bio-based copolymer may be either relativelylow in molecular weight (oligomeric) or relatively high in molecularweight. The number average molecular weight of the bio-based copolymermay range from about 1000 daltons to about 5,000,000 daltons or evenhigher, for instance. The dispersity of the bio-based copolymer may berelatively low (e.g., less than 1.5, for example) or relatively high(e.g., 1.5 or greater). The bio-based copolymer may be, for example,linear, branched or even cross-linked in structure, depending upon thepolymerization conditions, initiators, and monomers used. The bio-basedcopolymer may be a bio-based block copolymer, a random (statistical)bio-based copolymer, a graft bio-based copolymer, a brush bio-basedcopolymer, a star bio-based copolymer, or the like.

Bio-based copolymers in accordance with the present invention may besynthesized by any number of polymerization techniques including, butnot limited to, free-radical polymerization, controlled-radicalpolymerization, atom-transfer radical polymerization (ATRP) andvariants, single-electron transfer living radical polymerization(SET-LRP), reversible addition-fragmentation chain-transfer (RAFT)polymerization, ring-opening [metathesis] polymerization (RO[M]P),step-growth polymerization, cationic polymerization, anionicpolymerization, coordination polymerization, condensationpolymerization, emulsion polymerization, suspension polymerization,Ziegler-Natta polymerization, metallocene polymerization, group-transferpolymerization, reversible-deactivation radical polymerization, stablefree radical polymerization (SFRP), TEMPO polymerization,cobalt-mediated radical polymerization, nitroxide-mediated radicalpolymerization (NMP), catalytic chain-transfer polymerization, iniferterpolymerization, iodine-transfer polymerization (ITP), selenium-centeredradical-mediated polymerization, telluride-mediated polymerization,stibine-mediated polymerization, cationic ring-opening polymerization,and/or catalyst-transfer polycondensation.

In a particular preferred embodiment, RAFT polymerization is employed toprepare a bio-based copolymer in accordance with the present invention.A bio-based copolymer may be prepared by a method comprisingpolymerizing at least one bio-based monomer via RAFT, in the presence ofa free radical initiator and a chain transfer agent, to form thebio-based copolymer. One or more co-monomers may optionally also bepolymerized, either together as a mixture with the bio-based monomer(s)or separately (sequentially or step-wise). RAFT polymerization is one ofseveral kinds of reversible-deactivation radical polymerizations. Itmakes use of a chain transfer agent, such as a thiocarbonylthio compound(e.g., a dithioester, a thiocarbamate or a xanthate, such as2-cyano-2-propyl benzodithioate), to afford control over the generatedmolecular weight and polydispersity during a free-radicalpolymerization. The chain transfer agent mediates the polymerization ofthe bio-based monomer(s) and optional co-monomers via a reversiblechain-transfer process. The free-radical initiator may be, for example,an azo compound such as 2,2′-azobisisobutyronitrile (AIBN) or4,4′-azobis(4-cyanovaleric acid) (ACVA). The polymerization may becarried out in an organic solvent or mixture of organic solvents, suchas anisole, typically at temperatures ranging from about 40° C. to about120° C., or alternatively with no solvent (bulk). The polymerizationalso can be carried out as an emulsion-type polymerization wherein oneor more emulsification agents and a solvent (e.g., water) are used.Typical for RAFT polymerizations, 0.02 to 0.4 moles of initiator may beused for each mole of chain transfer agent; the moles of chain transferagent relative to the number of monomer(s) depends upon the targetmolecular weight and the monomer-to-polymer conversion. As with othercontrolled radical polymerization techniques, RAFT polymerizations canbe performed with conditions to favor low dispersity (narrow molecularweight distribution) and a pre-chosen molecular weight. RAFTpolymerization can be used to design polymers of complex architectures,such as linear block copolymers, comb-like, star, brush polymers,dendrimers and cross-linked networks.

Suitable co-monomers for forming the bio-based copolymers include, butare not limited to:

a). other lignin-based monomers (2,6-dimethoxyphenol, 2-methoxyphenol,and phenol derivatives with varying 4-position moieties) with similarstructures and functionalities as the phenol-based monomers;

b). styrenes (styrene, 4-bromostyrene, 4-fluorostyrene, etc.);alkylstyrenes (4-methylstyrene, 2-methylstyrene, 2,4-dimethylstyrene,4-ethylstyrene, benzhydrylstyrene, etc.);

c). phenyl [meth]acrylates with any number and position of substituentsand especially those also derived or obtained from lignin (e.g., phenyl[meth]acrylate, 2-methylphenyl [meth]acrylate, 4-ethylphenyl[meth]acrylate, 4-methylphenyl [meth]acrylate, 4-propylphenyl[meth]acrylate, guaiacol [meth]acrylate, creosol [meth]acrylate,4-ethylphenyl [meth]acrylate, 4-propylguaiacyl [meth]acrylate, eugenol[meth]acrylate, vanillin [meth]acrylate, trimethoxysilylpropyl[meth]acrylate, and the like);

d). alkyl [meth]acrylates with alkyl chain lengths anywhere from 1 to 36carbon atoms and any number of unsaturated bonds and especially thosethat are derived or obtained from bio-based resources (e.g., methyl[meth]acrylate, ethyl [methyl]acrylate, propyl [meth]acrylate, butyl[meth]acrylate, lauryl [meth]acrylate, palmitic [meth]acrylate, stearic[meth]acrylate, oleic [meth]acrylate, linoleic [meth]acrylate, and thelike);

e). other types of [meth]acrylates (e.g., [meth]acrylic acid,perfluorooctyl [meth]acrylates, hydroxymethyl [meth]acrylate,hydroxyethyl [meth]acrylates, poly(oligo-ethylene glycol)[meth]acrylate, 3-sulfopropyl [meth]acrylate potassium salt, and thelike);

f). terephthalates (e.g., polyethylene terephthalate, dimethylterephthalate, butylene terephthalate, trimethylene terephthalate,dioctyl terephthalate, cyclohexylenedimethylene terephthalate,terephthalic acid, terephthaloyl chloride, and the like);

g). amides, amines, diamides, and diamines (e.g., hexamethylenediamine,diaminohexane, ethylenediamine, para-phenylenediamine,4,4′-oxydianiline, putrescine, tetramethylene diamine,2-methylpentamethylene diamine, trimethyl hexamethylene diamine,xylylene diamine, 1,5-pentadiamine, 11-aminoundecanoic acid, aminolauricacid, bis[para-aminocyclohexyl] methane, diethyltoluenediamine,dimethylthiotoluenediamine, triethanolamine, and the like);

h). dichlorides (e.g., hexanedioyl dichloride);

i). nitriles (e.g., acrylonitrile, 2-propenenitrile, methacrylonitrile,2,6-dichlorobenzonitrile, pentachlorobenzonitrile);

j). carboxylic acids, including monocarboxylic acids, dicarboxylic acidsand polycarboxylic acids (e.g., adipic acid, sebacic acid, terephthalicacid, isophthalic acid, dodecanedoic acid, 4-hydroxybenzoic acid,6-hydroxynaphthalene-2-carboxylic acid, and the like);

k). lactones and lactone analogues (e.g., acetolactone, propiolactone,butyrolactone, valerolactone, caprolactone, dodecalactone, butenolide,macrolide, cardenolide, bufadienolide, lactide, cyclopentadenolide,coumarin, carvomenthide, menthide, tulipalin A, and the like),

l). lactams (e.g., caprolactam, laurolactam, vinylcaprolactam, and thelike);

m). maleates, malonates, and maleinates (e.g., dioctyl maleate, maleicacid, dimethyl maleate, maleic anhydride, diallyl maleate, diethylallylmalonate) and associated isomers, such as fumarates;

n). vinyls (e.g., vinyl chloride, vinyl bromide, vinyl fluoride,4-vinyl-styrene, ethylene, vinyl acetylene, vinyl naphthalene,vinylpyridine, vinylformamide, and the like);

o). vinyl esters (e.g., vinyl acetate, vinyl benzoate, vinyl4-tert-butylbenzoate, vinyl chloroformate, vinyl cinnamate, vinyldecanoate, vinyl nenodecanoate, vinyl nenononanoate, vinyl pivalate,vinyl propionate, vinyl stearate, vinyl trifluoroacetate, vinylvalerate, and the like);

p). vinyl amides (e.g., N-methyl-N-vinylacetamide, vinylformamide,vinylacetoamide, vinyl amide, and the like);

q). [meth]acrylamides (e.g., alkyl [meth]acrylamides, butyl[meth]acrylamide, diacetone [meth]acrylamide, diethyl [meth]acrylamide,diethyl [meth]acrylamide, ethyl [meth]acrylamide,hexamethylenebis[meth]acrylamide, hydroxymethy[meth]acrylamide,hydroxyethyl [meth]acrylamide, isobutoxymethyl [meth]acrylamide,isopropyl [meth]acrylamide, [meth]acrylamide, phenyl [meth]acrylamide,triphenylmethyl [meth]acrylamide, and the like);

r). thiols, dithiols, and polythiols (e.g., butanedithiol,benzenedithiol, biphenyldithiol, benzenetrithiol, decanedithiol,dithiothreitol, dithioerythritol, dimercaptonaphthalene, ethanedithiol,hexanedithiol, octanedithiol, propanedithiol, pentanedithiol,thiobisbenzenethiol, and the like);

s). enes, dienes, and olefins (e.g., terpenes, sesquiterpenes, ethylene,propene, butylene, isoprene, acetylene, myrcene, humulene,caryophyllene, farnesene, limonene, methylpentene, ethylene, propylene,butadiene, decalene, tetrafluoroethylene, hexafluoropropylene, pinene,chloroprene, acetylene, and the like);

t). allyl monomers (e.g., allyl acetate, allyl acetoacetate, allylalcohol, allylamine hydrochloride, allyl benzyl ether, allyl2-bromo-2-methylpropionate, allyl butyl ether, allyl chloroacetate,allyl cyanide, allyl cyanoacetate, allyl ether, allyl ethyl ether, allylmethyl carbonate, allyl methyl sulfone, allyloxybenzaldehyde,allyloxyethanol, allyoxy propanediol, allyl phenyl ether,allylphosphonic acid monoammonium salt, allyl trifuloroacetate,tert-butyl allyl carbamate, butyne, diallyl carbonate, methylsulfonylpropyne, propyne, trimethylolpropane [di]allyl ether, and the like,including the [meth]allyl analogues thereof);

u). azides and diazides (ethynylene diazide, glycidyl azide, etc.);

v). phosgene;

w). carbonates, including cyclic carbonates;

x). carbamates;

y). succinates;

z). alcohols, including diols and polyols (e.g.,4-amino-4-3-hydroxypropyl-1,7-heptanediol, benzenedimethanol,biphenyldimethanol, bis-hydroxymethyl-butyric acid, dihydrobenzoic acid,propanediol, cyclohexanediol, cyclopentanediol, dihydroxybenzophenone,dihydroxyacetophenone, dihydroxynaphthalene, butanediol, catechol,hexanediol, hexanetriol, hydrobenzoin, hydroquinone bis-2-hydroxyethylether, 2-hydroxymethyl-1,3-propanediol, pentanediol,phenyl-1,2-propanediol, ethylene glycol, pentaerythritol, glycerol,trimethylolpropane, and the like);

aa). silanes, silicones, and siloxanes (e.g., dimethyldichlorosilane,silatrane glycol, tetramethyl-tetravinylcyclotetrasiloxane, and thelike);

bb). ethers and vinyl ethers (e.g., vinyl ether, [di]glycidyl ether,butanediol [di]vinyl ether, butyl vinyl ether, chlorethyl vinyl ether,cyclohexyl vinyl ether, dodecyl vinyl ether, diethyl vinyl orthoformate,diethylene glycol [di]vinyl ether, phenyl vinyl ether, propyl vinylether, isobutyl vinyl ether, ethyl vinyl ether, ethylhexyl vinyl ether,ethylene glycol vinyl ether, and the like);

cc). vinyl sulfides (e.g., vinyl sulfide, phenyl vinyl sulfide,4-chlorophenyl vinyl sulfide, bromphenyl vinyl sulfide, ethyl vinylsulfide, and the like);

dd). isocyanates, including diisocyanates and polyisocyanates (e.g.,diisocyanatobutane, diisocyanatododecane, diisocyanatooctane,hexamethylene diisocyanate, cyclohexylene diisocyanate, phenylenediisocyanate, tolylene diisocyanate, toluene diisocyanate, methylenediphenyl diisocyanate, isophorone diisocyanate, and the like);

ee). epoxides (e.g., ethylene oxide, allyl glycidyl ether, butadienediepoxide, butanediol diglycidyl ether, butyl glycidyl ether, tert-butylglycidyl ether, chlorophenyl glycidyl ether, cyclohexene oxide,cyclopentene oxide, dicyclopetadiene dioxide, dieldrin,diepoxycyclooctane, diepoxyoctane, N,N-diglycidyl-4-glycidyloxyaniline,epoxybutane, epoxybutene, epoxydodecane, epoxyhexane, epoxyhexene,epoxynorbornane, epoxyoctane, epoxypentane, epoxy-phenoxypropane,epoxypropyl benzene, epoxypropyl phthalimide, epoxytetradecane,ethylhexyl glycidyl ether, furfuryl glycidyl ether, glycidyl4-methoxyphenyl ether, glycidyl methylphenyl ether, methyl vinyloxirane,pinene oxide, propylene oxide, resorcinol diglycidyl ether, stilbeneoxide, styrene oxide, and the like);

ff). norbornenes (e.g., dicyclopentadiene, norbornene,bicycloheptadiene, and the like); and

gg). anhydrides (e.g., [meth]acrylic anhydride, maleic anhydride,citraconic anhydride, crotonic anhydride, itaconic anhydride,methylglutaric anhydride, methylphthalic anhydride, methylsuccinicanhydride, naphthalic anhydride, phenylglutaric anhydride, phenylmaleicanhydride, and the like);

as well as combinations or mixtures of any two or more of theabove-mentioned co-monomers.

In an embodiment of the method, the step of forming a bio-basedcopolymer comprises forming a bio-based block copolymer, and wherein theco-monomer-based polymeric block comprises, in polymerized form, atleast one of ethylene oxide, propylene oxide, (oligo-oxyethylene)[meth]acrylate, styrene trifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt or comprisesat least one of oligo-oxyethylene, oligo-oxypropylene, poly(ethyleneoxide) or poly(propylene oxide).

In another embodiment, the step of forming a bio-based block copolymercomprises forming a triblock copolymer, and wherein the co-monomer-basedpolymeric block is a midblock formed by polymerizing a co-monomercomprising an alkyl [meth]acrylate, a diene, or an olefin and whereinthe at least one bio-based monomer is polymerized forming at least oneof the two glassy end blocks.

In another embodiment, the step of forming a bio-based copolymercomprising co-polymerizing at least one bio-based monomer correspondingto formula (II) with one or more co-monomers other than the at least onebio-based monomer. In one embodiment, the one or more co-monomerscomprises a co-polymerizable ion-conducting co-monomer, and wherein thecopolymer is a random, statistical, graft, star, brush or cycliccopolymer. Suitable co-polymerizable ion-conducting co-monomer includes,but are not limited to, at least one of (oligo-oxyethylene)[meth]acrylate, styrene trifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt.

The bio-based copolymer may, in a preferred embodiment, be athermoplastic, but may in another embodiment be a thermoset. Thebio-based monomers of the present invention also are useful in thepreparation of thermoplastic elastomers, in particular thermoplasticelastomers which are bio-based block copolymers in which one or moreblocks are blocks of one or more bio-based monomers providing a “hard”polymerized segment having a relatively high T_(g) (e.g., a T_(g) of atleast 50° C. or more preferably a T_(g) of at least 100° C.) and one ormore blocks are blocks of a monomer or mixture of monomers providing a“soft” polymerized segment having a relatively low T_(g) (e.g., a T_(g)of less than 30° C. or more preferably a T_(g) of less than 0° C.). Asused herein the term “glassy end block” refers to those end blocks,which when formed into an independent polymer would result in a glassypolymer at the use temperature.

The bio-based copolymer may be comprised, in various embodiments of theinvention, of at least 1%, at least 5%, at least 10%, at least 20%, atleast 30%, at least 40%, at least 50%, at least 60%, at least 70%, atleast 80%, at least 90%, at least 95%, or at least 99% by weight or 100%by weight of bio-based monomer(s) in polymerized form. The balance ofthe bio-based copolymer may be comprised of one or more of theabove-mentioned co-monomers, in polymerized form, as well as initiatormoieties and/or crosslinker moieties (to be extent initiators and/orcrosslinking agents are used in the preparation of the bio-basedcopolymer and end up being incorporated into the bio-based copolymer asa result of the polymerization).

The bio-based copolymer may also be grafted to or grafted fromparticles, nanoparticles, and/or surfaces including, but not limited to,linoleum, granite, gold, concrete, silica, silicon dioxide,poly(dimethylsiloxane), poly(norbornene)s, poly(carbonate)s, graphene,graphite, diamond, garnet, ruby, emerald, topaz, talc, glass, zinc,steel, asphalt, ceramics, porcelain, tin, aluminum, foil, cloth, cotton,cellulosic fibers, lignin fibers, tetrafluoroethylene polymers,polyimides, quartz, nylon, silk, rayon, carbon nanotubes, nanowires,clay, and other organic, inorganic, or metallo-organic surfaces ofvarying roughness, flexibility, strength, and size. As used herein, theterm “metallo-organic”refers to materials containing metal-organic bondsincluding, but not limited to metal organic frameworks and metal organicpolyhedral.

The bio-based copolymer may also be a bulk or composite material. Manydifferent nanoparticles and nanofibers may be blended into a bio-basedcopolymer before, during or after polymerization to impart different orenhanced properties to the product material. Nanoparticles andnanofibers of any of the above-mentioned types of materials orsubstances may be utilized as media from which, or to which, a bio-basedcopolymer may be synthesized or attached/grafted.

The bio-based copolymers, as disclosed hereinabove, may be used forvarious applications, especially as binders and electrolytes for lithiumion batteries and in articles as adhesives or as components offormulated adhesives.

A Bio-Based Copolymer for Use as a Binder or an Electrolyte

In an aspect, there is provided a bio-based copolymer comprising atleast one polymerizable bio-based monomer having a structurecorresponding to formula (II) as disclosed hereinabove and at least oneion-conducting co-monomer other than the polymerizable bio-basedmonomer. The bio-based copolymer can be a random, a statistical, or abio-based block copolymer. However, in other embodiments, the bio-basedcopolymer can be a graft, a star, a brush, or a cyclic bio-basedcopolymer.

In one embodiment, the bio-based copolymer is a bio-based blockcopolymer. In particular, bio-based block copolymers of the presentinvention for use as polymer electrolytes and or binders provide severaladvantages, including but not limited to, being derived from renewableresources (bio-derived), adhesivity, thermal stability, and beingoperable at higher temperature than conventional materials such aspolystyrene, thereby increasing stability and providing an opportunityto increase conductivity by increasing operating temperature.Furthermore, the bio-based block copolymers of the present invention canbe capable of self-assembly into periodically ordered structures, whichin turn provides simultaneous control over both ionic transport andmechanical strength (and thermal stability).

In an embodiment, the bio-based copolymer is a block copolymercomprising at least one bio-based polymeric block comprising, inpolymerized form, at least one bio-based monomer corresponding toformula (II) and an ion-conducting co-monomer-based polymeric block. Insuch embodiments, the ion-conducting co-monomer-based polymeric blockcomprises, in polymerized form, at least one of ethylene oxide,propylene oxide, (oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt or comprisesat least one of oligo-oxyethylene, oligo-oxypropylene, poly(ethyleneoxide), or poly(propylene oxide).

In another embodiment, the at least one ion-conducting co-monomer is aco-polymerizable ion-conducting co-monomer comprising at least one of(oligo-oxyethylene) [meth]acrylate, styrenetrifluoromethanesulfonylimide lithium salt,1-(3-(methacryloyloxy)-propylsulfonyl)-1-(trifluoromethylsulfonyl)imidelithium salt, and 3-sulfopropyl methacrylate lithium salt, and whereinthe resulting bio-based copolymer is a random, statistical, graft, star,brush or cyclic copolymer. According to certain embodiments, theco-polymerizable ion-conducting co-monomer may have the followingstructure:H₂C═C(R)C(═O)—O—(CH₂CH₂O)_(x)R′wherein R is H or CH₃, R′ is H or alkyl (e.g., C₁-C₆ alkyl, such asmethyl), and x is at least 2 (e.g., 2 to 1000). In certain embodiments,x is in the range of 2-1000, or 4-20, or 6-12.

Any suitable overall molar ratio of bio-based monomer to ion-conductingco-monomer in the bio-based copolymer may be used, including but notlimited to, for example, within a range from 1:30 to 30:1, a range from1:20 to 20:1, or a range from 1:10 to 10:1.

The number average molecular weights of the individual blocks orsegments in the bio-based copolymer may be, for example, within a rangeof 1,000 to 500,000 g/mol. In one embodiment, the number averagemolecular weight of the bio-based monomer block is 5,000 to 25,000g/mol, and the number average molecular weight of the ion-conductingco-monomer block is 1,000 to 15,000 g/mol.

In one embodiment, the bio-based monomer block portion(s) of thebio-based copolymer may be characterized as being essentially free orentirely free of any polymerized units of ion-conducting co-monomer. Inone aspect, the bio-based monomer block portion(s) contain onlypolymerized units of one or more types of bio-based monomer. However, inother embodiments of the invention, it is possible for the bio-basedmonomer blocks to contain relatively small amounts (e.g., up to about 20weight %) of polymerized units of monomers other than bio-based monomerssuch as, for example, [meth]acrylates, vinyl monomers, vinyl aromaticmonomers, [meth]acrylamides, dienes, acrylonitrile, olefins and thelike.

In one embodiment, the ion-conducting co-monomer block portion(s) of thebio-based copolymer may be characterized as being essentially free orentirely free of any polymerized units of bio-based monomer. In oneaspect, the ion-conducting co-monomer block portion(s) contain onlypolymerized units of one or more types of ion-conducting co-monomer.However, in other embodiments of the invention, it is possible for theion-conducting co-monomer blocks to contain relatively small amounts(e.g., up to about 20 weight %) of polymerized units of monomers otherthan ion-conducting co-monomers such as, for example, hydroxyalkylesters of (meth)acrylic acid, (meth)acrylic acid, mono(oxyalkylene)acrylates and the like.

Generally speaking, it will be desirable for the bio-based copolymer tohave a relatively low dispersity (sometimes also referred to aspolydispersity index and calculated by dividing the weight averagemolecular weight by the number average molecular weight). For example,the dispersity of the bio-based copolymer in various embodiments of thepresent invention may be less than 1.5, less than 1.4, less than 1.3 orless than 1.2. Number average molecular weight and weight averagemolecular weight may be measured using gel permeation chromatography(GPC) and calibration standards such as polystyrene.

In one desirable embodiment of the invention, the composition of thebio-based copolymer (e.g., bio-based monomer and ion-conductingco-monomer used to prepare the bio-based copolymer, the molecular weightcharacteristics of the overall bio-based copolymer and the individualblocks or segments) is selected so as to provide a bio-based copolymerthat is solid at room temperature and thermoplastic.

In one embodiment, the co-monomer-based polymeric block comprises apoly((oligo-oxyethylene) [meth]acrylate) block, and the bio-basedcopolymer is a diblock bio-based copolymer having the followingstructure (III) or a triblock bio-based copolymer having the followingstructure (IV):

wherein x is in the range of 2-1000, or 4-20, or 6-12; n in the range of10-500, or 15-100, or 20-50; and m in the range of 10-1000, or 15-200,or 20-50.

In an aspect of the present invention, a binder for a battery, such aslithium ion battery, comprises the bio-based copolymer as describedhereinabove. In another aspect, an electrode is provided comprising thebinder and an electrode active material.

In yet another aspect, a polymer electrolyte is provided, comprising thebio-based copolymer of the present invention, as described hereinaboveand at least one salt. The polymer electrolyte can contain a mixture oftwo or more aforementioned bio-based copolymers with differentstructural units, different molecular weights, etc. The polymerelectrolyte may also contain one or more types of polymers other thanthe bio-based copolymers described hereinabove. In one embodiment, thepolymer electrolyte is solid (i.e., solid at room temperature). Inanother embodiment, the polymer electrolyte is essentially free or freeof any volatile substances, such as organic solvents.

The at least one salt may include at least one lithium salt. Anysuitable salt may be used, including but not limited to, LiBr, LiCl,LiClO₄, LiPF₆, LiAsF₆, LiSbF₆, LiBF₄, LiCF₃SO₃, LiN(FSO₂)₂,LiN(CF₃SO₂)₂, LiN(C₂F₅SO₂)₂, LiC₆F₃N₄, LiC(CF₃SO₂)₃, Li₂B₁₀Cl₁₀,LiB(OCH₃)₄, LiB(C₂O₄)₂, LiB(CN)₄, LiBC₂O₄F₂, LiB(C₃O₄F)₂, lithiumacetate, and LiAlCl₄.

The quantity added of the electrolyte salt may typically be within arange from 0.005 to 80 mol %, e.g., from 0.01 to 50 mol %, relative tothe quantity of (oligo-oxyethylene) units within the bio-basedcopolymer. Where the salt is a lithium salt, the molar ratio of [oxygenatoms in the (oligo-oxyethylene) units in the bio-based copolymer]:[Li]may be, for example from 1:1 to 100:1. In one embodiment, the molarratio of oxygen atoms in the [(oligo-oxyethylene) units in the bio-basedcopolymer]:[Li] is 20:1.

In an embodiment, the aforementioned polymer electrolyte hasconductivity in the range of 10⁻¹⁰-10⁻¹ or 10⁻⁹-10⁻² or 10⁻⁸-10⁻³ S/cm.

In another embodiment, the aforementioned binder has conductivity in therange of 10⁻¹⁰-10⁻¹ or 10⁻⁹-10⁻² or 10⁻⁸-10⁻³ S/cm.

A polymer electrolyte of the present invention can be produced bycombining and mixing (complexing) an electrolyte salt with anaforementioned bio-based copolymer. There are no particular restrictionson the method used for this process, and suitable methods include amethod in which the bio-based copolymer and the electrolyte salt aredissolved in a suitable solvent such as tetrahydrofuran, methyl ethylketone, acetonitrile, ethanol, or dimethylformamide (with the solventlater being removed), and a method in which the bio-based copolymer andthe electrolyte salt are mixed together mechanically, either at roomtemperature or under heat.

Molding the aforementioned solid polymer electrolyte into sheet,membrane, film or other form may be performed using any of thetechniques known in the polymer electrolyte art. For example, asheet-like solid polymer electrolyte can be produced by any of a varietyof coating techniques including roll coating, curtain coating, spincoating, dipping, or casting, and using one of these techniques, a filmof the solid polymer electrolyte is formed on the surface of asubstrate, and the substrate can be subsequently removed to yield thesolid polymer electrolyte sheet as necessary.

Also, provided herein is an electrochemical device, in accordance withvarious embodiments of the present invention, the electrochemical devicecomprising an electrode in electrical contact with the aforementionedpolymer electrolyte, wherein at least one of the electrode and thepolymer electrolyte comprises the bio-based copolymer of the presentinvention, as disclosed herein above. In one embodiment of theelectrochemical device, only the electrode comprises the bio-basedcopolymer of the present invention. In another embodiment of theelectrochemical device, only the polymer electrolyte comprises thebio-based copolymer of the present invention. In yet another embodimentof the electrochemical device, both the electrode and the polymerelectrolyte comprise the bio-based copolymer of the present invention.

In one embodiment, the electrochemical cell, such as a lithium ionbattery comprises an electrode in electrical contact with theaforementioned polymer electrolyte, wherein at least one of theelectrode and the polymer electrolyte comprises the bio-based copolymerof the present invention, for example a diblock bio-based copolymer,poly(guaiacyl methacrylate)-b-poly(oligo-oxyethylene methacrylate)(P(GMA)-b-P(OEM) having the following structure (VI) or a triblockbio-based copolymer, poly(guaiacylmethacrylate)-b-poly(oligo-oxyethylene methacrylate)-b-poly(guaiacylmethacrylate) (P(GMA)-b-P(OEM)-b-P(GMA)) having the following structure(VII):

wherein x is in the range of 2-1000, or 4-20, or 6-12; n in the range of10-500, or 15-100, or 20-50; and m in the range of 10-1000, or 15-200,or 20-50.

Depending on the ratio of n and m as well as the overall degree ofpolymerization (n+m in the case of a diblock or 2n+m in the case of atriblock), nanoscale morphologies including spheres, hexagonally-packedcylinders, double gyroid, or lamellae are achievable. Domain spacing ofthe bio-based copolymer is in the range of 5-100 nm, or 10-80 nm, or20-50 nm.

To use the bio-based copolymer as a binder, the electrode activematerial, conductive carbon, and the bio-based copolymer are thoroughlymixed in n-methyl-2-pyrrolidone to prepare a slurry. The slurry isspread on a copper foil and dried at 150° C. overnight.

An Article Comprising an Adhesive Composition

In an aspect of the invention, an article is provided comprising anadhesive composition adhesively disposed over a substrate. In anembodiment, the adhesive composition comprises a bio-based blockcopolymer in accordance with the invention and optionally at least oneadditive. The bio-based block copolymer may include at least onebio-based polymeric block comprising, in polymerized form, at least onepolymerizable bio-based monomer having a structure corresponding toformula (II):

R₁ can be hydrogen, methyl, ethyl, n-propyl, i-propyl, or propylene. R₂can be a substituent comprised of at least one polymerizable functionalgroup that is an ethylenically unsaturated functional group, asdisclosed hereinabove. R₃ and R₄ can both be H, or can both be methoxy,or can be hydrogen and methoxy. The ethylenically unsaturated functionalgroup has been polymerized to form at least one bio-based polymericblock. The bio-based block copolymer also includes a co-monomer-basedpolymeric block comprising, in polymerized form, at least onepolymerizable co-monomer other than a polymerizable bio-based monomer.Any suitable polymerizable co-monomer may be used including, but notlimited to, an alkyl [meth]acrylate. In an embodiment, the at least onepolymerizable co-monomer includes an alkyl [meth]acrylate, where thealkyl group may be selected from the group consisting of C1 to C₁₈ alkylgroups. In an embodiment, the alkyl group is a butyl group. In anembodiment, R₁ is a propyl group.

In some embodiments, the block polymer may be a triblock bio-basedcopolymer comprising the alkyl [meth] acrylate as the polymerizableco-monomer in polymerized form for the midblock and the at least onepolymerizable bio-based monomer in polymerized form as one or both ofthe glassy end blocks. An exemplary triblock bio-based copolymer can bepoly(4-propylsyringyl acrylate-b-butyl acrylate-b-4-propylsyringylacrylate) having the following structure (V):

and

wherein n is in the range of 10-500, or 15-100, or 20-50; and m in therange of 10-1000, or 15-200, or 20-50

In an embodiment, the adhesive composition can be a pressure sensitiveadhesive composition.

In another embodiment, one or more additives are present in the adhesivecomposition, in addition to the bio-based copolymer, and may be selectedfrom the group consisting of tackifiers, plasticizers, viscositymodifiers, photoluminescent agent, anti-counterfeit and UV-reactiveadditives, dyes/pigments, anti-static materials, surfactants, andlubricants. In another embodiment, the adhesive composition is free oftackifier.

The article of the present invention may include any suitable substrate,including but not limited to, a polymeric film, a paper label, a tapebacking, a graphic article, a plastic article, a metal article, a wounddressing, a protection film or tape, or a release liner.

Within this specification, embodiments have been described in a waywhich enables a clear and concise specification to be written, but it isintended and will be appreciated that embodiments may be variouslycombined or separated without departing from the invention. For example,it will be appreciated that all preferred features described herein areapplicable to all aspects of the invention described herein.

In some embodiments, the invention herein can be construed as excludingany element or process step that does not materially affect the basicand novel characteristics of the composition or process. Additionally,in some embodiments, the invention can be construed as excluding anyelement or process step not specified herein.

Although the invention is illustrated and described herein withreference to specific embodiments, the invention is not intended to belimited to the details shown. Rather, various modifications may be madein the details within the scope and range of equivalents of the claimsand without departing from the invention.

EXAMPLES

General Procedure of Lignocellulosic Biomass Depolymerization,Purification, and Characterization.

FIG. 1 shows a general reaction scheme for depolymerizing poplar wood inmethanol with a commercially available Ru/C catalyst, which is effectiveand selective to C—O bonds cleavage.^(27,40)

In particular, poplar wood powder (1 g, particle size <0.5 mm), methanol(20 mL), and catalyst (5 wt % Ru/C, Sigma-Aldrich, 100 mg) were added toa 50 mL high-pressure Parr reactor. The reactor was purged with H₂ threetimes and then pressurized with H₂ to a pressure of 40 bar. The reactorwas heated to 250° C. and held for 15 h while stirring. After thereaction was completed, the reactor was cooled to room temperature withan external flow of compressed air. The solution containing aromaticmonomers was separated from the resultant slurry by filtration. Thesolid (cellulose, catalyst) was washed with methanol (10 mL, 3 times),and the solution was combined with the previous methanol solution.Methanol was removed using a rotary evaporator at 60° C., and theresidue was extracted with cyclohexane (10 mL, 3 times) to obtain pure4-propylsyringol (4pS) and 4-propylguaiacol (4pG) mixture in thecyclohexane phase (light brown color). The aromatic monomers from thepoplar wood feedstock were analyzed before and after the cyclohexaneextraction on an Agilent 7890B series gas chromatograph (GC) equippedwith a HP5 capillary column and an Agilent 5977A series massspectroscopy detector (FIG. 1 ). The following operating conditions wereused: injection temperature of 250° C., a column temperature program of50° C. (held for 1 min), heating ramp to 300° C. at 15° C. min⁻¹, andthen 300° C. (held for 7 min). The detector temperature was 290° C.

FIG. 2A shows that two prominent monophenolic compounds,4-propylsyringol (4pS) and 4-propylguaiacol (4pG), were collected, alongwith small portions of other dihydroxyl-containing components. FIG. 2Bshows that following a simple extraction with cyclohexane, high puritymonophenolic compounds, 4pS and 4pG, were obtained with relative massfractions of 0.6 and 0.4, respectively, at a total yield of 10 wt % onthe basis of weight of dry poplar wood. The removal of the dihydroxylspecies is critical to prevent the formation of a crosslinked networkduring the polymerization process. 4pS and 4pG then were efficientlyfunctionalized with either acrylate or methacrylate groups, followed bypolymerization via a scalable RAFT polymerization approach, as describedbelow.

Synthesis and Characterization of Lignin-Based Monomers:4-Propylsyringyl Acrylate (4pSA), 4-Propylguaiacyl Acrylate (4pGA),4-Propylsyringyl Methacrylate (4pSMA), and 4-Propylguaiacyl Methacrylate(4pGMA)

The aromatic monomer mixture, comprising 4pS and 4pG, was acrylated withacryloyl chloride for the synthesis of acrylates and methacryloylchloride for the synthesis of methacrylates, following a procedureadapted from the disclosure of the following article authored by theinventors, is hereby incorporated by reference in its entirety for allpurposes: Wang et. al., “Effect of methoxy substituent position onthermal properties and solvent resistance of lignin-inspiredpoly(dimethoxyphenyl methacrylate)s,” ACS Macro Letters 2017, 6 (8),802-807.

The aromatic monomers and triethylamine (1.2 mol eq, Fisher Scientific,99%) were dissolved in dichloromethane (DCM, anhydrous, FisherScientific) in a three-neck round bottom flask. The mixture was spargedwith argon for 15 min while the flask was immersed in an ice-water bath.A solution of acryloyl chloride (1.2 mol eq, Sigma Aldrich, 97%) in DCMwas added drop wise using a constant pressure dropper. The reaction wasleft to proceed overnight, after which, a white precipitant was filteredby vacuum filtration and discarded. The DCM permeate phase was washedconsecutively with solutions of saturated sodium bicarbonate, 1.0 M NaOH(twice), 1.0 M HCl, and deionized water. DCM was removed by rotaryevaporation, and the monomers were further purified by flashchromatography using silica gel (Standard Grade, 230×400 mesh, 60 Å)with ethyl acetate/hexanes mixture as an eluent (ethyl acetate volumefraction gradually increased from 0% to 10%). Two pure products,4-propylsyringyl acrylate (4pSA) and 4-propylguaiacyl acrylate (4pGA),were obtained.

¹H NMR (CDCl₃, 600 MHz, δ) for:

4pSA: 6.62 (1H, d), 6.44 (2H, aromatic, s), 6.40 (1H, q), 6.00 (1H, d),3.80 (6H, s), 2.56 (2H, t), 1.65 (2H, m), 0.97 (3H, t); and

4pGA: 6.96 (1H, d), 6.79 (1H, d), 6.76 (1H, d), 6.60 (1H, d), 6.35 (1H,q), 5.99 (1H, d), 3.81 (3H, s), 2.58 (2H, t), 1.65 (2H, m), 0.96 (3H,t).

Aromatic monomers (4pS and 4pG) also were methacrylated using the sameprocedure, except substituting methacryloyl chloride (1.2 mol eq, AlfaAesar, 97%) for acryloyl chloride. Two products, 4-propylsyringylmethacrylate (4pSMA) and 4-propylguaiacyl methacrylate (4pGMA) werecollected.

¹H NMR (CDCl₃, 600 MHz, δ) for:

4pSMA: 6.45 (2H, s), 6.40 (1H, s), 5.76 (1H, t), 3.82 (6H, s), 2.58 (2H,t), 2.10 (3H, s), 1.65 (2H, m), 0.97 (3H, t); and

4pGMA: 6.95 (1H, d), 6.78 (1H, d), 6.76 (1H, d), 6.34 (1H, s), 5.72 (1H,t), 3.81 (3H, s), 2.57 (2H, t), 2.06 (3H, s), 1.65 (2H, m), 0.96 (3H,t).

Synthesis of Lignin-Based Polymers: Poly(4-Propylsyringyl Acrylate)(P(4pSA)), Poly(4-Propylguaiacyl Acrylate) (P(4pGA)),Poly(4-Propylsyringyl Methacrylate) (P(4pSMA)), andPoly(4-Propylguaiacyl Methacrylate) (P(4pGMA))

Poly(4pSA) and poly(4pGA) were synthesized by RAFT polymerization, usinga procedure described in the literature.¹⁸ The initiator,2,2′-azobisisobutyronitrile (AIBN, Sigma-Aldrich, 98%), wasrecrystallized twice from methanol prior to use. The chain transferagent (CTA),3,5-bis(2-dodecyl-thiocarbonothioylthio-1-oxopropoxy)benzoic acid(BTCBA, Sigma Aldrich, 98%), was used as received. The polymerizationsolvent, anisole (Sigma-Aldrich, ≥99.7%) with 5 wt %N,N-dimethylformamide (DMF, Sigma-Aldrich, ≥99.9%), was prepared andstored on molecular sieves to minimize water content.

The monomer (4pSA or 4pSGA), BTCBA and AIBN were dissolved in thepolymerization solvent and transferred to a pressure vessel. Thereaction mixture was degassed by three freeze-pump-thaw cycles,backfilled with argon to a pressure of 3 psi, sealed with a stopcock,and immersed in an oil bath (70° C.) with vigorous stirring. Thereaction was quenched at a predetermined time (typical reaction time was6-7 h) by immersing the pressure vessel in liquid nitrogen.Tetrahydrofuran (THF, Fisher Scientific, certified) was added to themixture, and the polymer was purified by precipitating into excesshexanes at least two times to ensure no monomer remained (confirmed by1H NMR spectroscopy).

The same procedure was employed in the synthesis of P(4pSMA) andP(4pGMA), except that 2-cyano-2-propyl benzodithioate (CPB, STREMChemicals, 97%) was utilized as the CTA.

Synthesis of Bio-Based Diblock Copolymer: Poly(4-PropylsyringylMethacrylate-Co-4-Propylguaiacyl Methacrylate) P(4pSMA-Co-4pGMA)

A bio-based copolymer of 4pSMA and 4pGMA (poly(4pSMA-co-4pGMA)) also wassynthesized to demonstrate the feasibility of making polymers from theoriginal biomass mixture, without fractionation into individualcomponents. The monomer ratio of 4pSMA/4pGMA (0.60/0.40) and the segmentcontent in the polymer (0.58/0.42, as determined via ¹H NMRspectroscopy) were consistent, suggesting a random incorporation of eachsubstituent in the polymer backbone.

The bio-based copolymer (poly(4pSMA-co-4pGMA) was made following theprocedure described hereinabove for the synthesis of poly(4pSA) andpoly(4pGA), except that a mixture of 4pSMA and 4pGMA at a ratio of0.6/0.4 was fed instead of the single monomers (4pSA or 4pGA).

The characteristics of the bio-based polymers derived from lignin-basedmonomers: polymers, poly(4-propylsyringyl acrylate) (P4pSA),poly(4-propylguaiacyl acrylate) (P4pGA), poly(4-propylsyringylmethacrylate) (P4pSMA), and poly(4-propylguaiacyl methacrylate)(P4pGMA), are summarized in Table 1.

TABLE 1 Characteristics of lignin-derived polymers Polymer M_(n) ^(a)(kg mol⁻¹) D^(b) T_(g) ^(c) (° C.) P(4pSA) 19.1 1.44  98 P(4pSMA) 30.41.16 169 P(4pGA) 29.6 1.29  56 P(4pGMA) 12.4 1.29  80 P(4pSMA-co-4pGMA)(0.58/0.42)^(d) 26.7 1.26 135 ^(a))Number-average molecular weight,determined by size-exclusive chromatography (SEC); ^(b))Dispersity,determined by SEC; ^(c))Determined by differential scanning calorimetry(DSC); ^(d))A mixture of 4pSMA and 4pGMA was fed, and the numbers denotethe composition of 4pSMA and 4pGMA (mol/mol) in the resulting bio-basedcopolymer.

As summarized in Table 1, the glass transition temperatures (T_(g))s ofP(4pSA) (98° C.) and P(4pSMA) (169° C.) were attractive relative topolystyrene (PS, T_(g)˜100° C.) and PMMA (T_(g)˜110° C.), as T_(g)s oflignin-derived polymers are tunable and can be significantly higher thanpolystyrene, which provides greater thermal stability. It should benoted that the T_(g)s of P(4pGA) (56° C.) and P(4pGMA) (80° C.) with onemethoxy group at the ortho position were lower than those of P(4pSA) andP(4pSMA). Without wishing to be bound by any particular theory, it isbelieved that the existence of two ortho methoxy groups constrainedrotation of the pendant groups and raised the T_(g)s of thedimethoxy-based polymers.

The bio-based copolymer poly(4pSMA-co-4pGMA) had a T_(g) of 135° C.,which was close to that estimated for a random bio-based copolymer of4pSMA and 4pGMA on the basis of the Flory-Fox equation (˜127° C.).

The thermal behavior of these lignin-based polymers, copolymers andblock copolymers, especially the desirable glass transitiontemperatures, provides an initial indication of their utility in the PSAmaterials.

Synthesis of Bio-Based Triblock Copolymer: Poly(4-PropylsyringylAcrylate-b-Butyl Acrylate-b-4-Propylsyringyl Acrylate)(P(4pSA-b-BA-b-4pSA)) (Also Referred Herein as SaBSa)

To demonstrate the ease of producing model consumer products directlyfrom raw biomass depolymerization products, a triblock polymer wassynthesized with P(4pSA) as the glassy end blocks and poly(n-butylacrylate) (PBA) as the midblock, generating poly(4pSA-b-BA-b-4pSA)

In particular, the triblock bio-based copolymer was synthesized withP(4pSA) as the glassy end blocks and PBA as the midblock, generating(poly(4-propylsyringyl acrylate-co-butyl acrylate-co-4-propylsyringylacrylate)) (P(4pSA-b-BA-b-4pSA)) to demonstrate the ease of producingmodel consumer products directly from raw biomass depolymerizationproducts.

The triblock bio-based copolymer P(4pSA-b-BA-b-4pSA) was synthesized ina two-step RAFT polymerization, using BTCBA as the CTA. PBA wassynthesized first, following the general procedure describedhereinabove, except that the polymer was precipitated into coldmethanol. Then, PBA was chain-extended with the monomer 4pSA to make theP(4pSA-b-BA-b-4pSA) triblock bio-based copolymer. P(4pSA-b-BA-b-4pSA)was isolated by precipitation in cold methanol three times to removeunreacted 4pSA and dried in vacuum for 2 days at 40° C.

¹H NMR spectrum of P(4pSA-b-BA-b-4pSA) with TMS as an internal standard(CDCl₃, 600 MHz, δ) is shown in FIG. 3 . The weight percentage of the4pSA blocks was calculated from the ¹H NMR data, as follows:

${\frac{{{area}(a)} \times {{MW}\left( {4{pSA}} \right)}}{{{{area}(a)} \times {{MW}\left( {4{pSA}} \right)}} + {{{area}(A)} \times {{MW}\left( {n - {BA}} \right)}}} \times 100\%} = {{\frac{2 \times 250.29}{{2 \times 250.29} + {13.94 \times 128.17}} \times 100\%} = {22\%}}$

-   -   where the area(a) and area(A) refer to the area under the peaks        labeled a and A, respectively, in FIG. 3 .

Comparative Analysis of Bio-Based Triblock Copolymer(P(4pSA-b-BA-b-4pSA)) of the Present Invention with a CommerciallyAvailable Triblock Copolymer (P(MMA-b-BA-b-MMA)) for Use in PressureSensitive Adhesive (PSA) Applications

FIG. 4 shows the SEC chromatograms of PBA and P(4pSA-b-BA-b-4pSA). Theclean shift in molecular weight from before (M_(n)=49.7 kg mol⁻¹,Ð=1.11) to after addition of the P(4pSA) end blocks clearly indicatesthe ability to chain extend using the biomass-derived monomers, whileretaining substantial control over the polymerization. The finalP(4pSA-b-BA-b-4pSA) triblock bio-based copolymer had a M_(n) of 66.4 kgmol⁻¹, a Ð of 1.15, and a P(4pSA) weight percentage of 22%. Thesemacromolecular characteristics were targeted to approximate a commercialpoly(MMA-b-BA-b-MMA) (P(MMA-b-BA-b-MMA Kurarity LA2140e, M_(n)=66.9 kgmol⁻¹, Ð=1.12, 23 wt % PMMA) produced by Kuraray Co., Ltd for use inPSAs.

The thermal behavior and phase separation characteristics ofP(4pSA-b-BA-b-4pSA) and P(MMA-b-BA-b-MMA) were compared by measuringT_(g)s and size-scales of microphase separation via DSC and small-angleX-ray scattering (SAXS), respectively. T_(g)s corresponding to thePBA-rich domains were detected at −45° C. (P(4pSA-b-BA-b-4pSA)) and −49°C. (P(MMA-b-BA-b-MMA)), as shown in FIG. 5 . No clear transition ofP(4pSA) (˜98° C.) or P(MMA) (˜110° C.) was found. Without wishing to bebound by any particular theory, it is believed that this is likely dueto the low weight fraction of the end block in each polymer (˜11 wt %for each end block). However, the similarity of T_(g) of PBA block inthe triblock bio-based copolymer to that of PBA homopolymer issuggestive of block immiscibility and microphase separation. Nanoscalephase separation in the lignin-based P(4pSA-b-BA-b-4pSA) triblockbio-based copolymer was confirmed by SAXS. A principal scattering peak(q*) at 0.030 Å⁻¹, corresponding to a domain spacing (D*=2n/q*) of ˜21nm, was clearly visible in the 1-D azimuthally integrated SAXS data, asshown in FIGS. 6A and 6B. A similar scattering pattern also was obtainedfor P(MMA-b-BA-b-MMA) (FIGS. 6C and 6D), which suggested a domainspacing of ˜20 nm.

The overall thermal stability of P(4pSA-b-BA-b-4pSA) was evaluated bythermogravimetric analysis (TGA), and the bio-derived triblock exhibitedexcellent thermal stability. P(4pSA-b-BA-b-4pSA) was thermally stable upto 337° C. under air (the temperature at which the weight of the polymerwas reduced by 5%), as shown in FIG. 7 . In comparison, the thermalstability of P(MMA-b-BA-b-MMA) characterized in air flow, was muchlower, with a 5% degradation temperature of 285° C., as shown in FIG. 7. Furthermore, when comparing P(4pSA-b-BA-b-4pSA) to other modelbio-inspired PSAs reported in the literature, the lignin-derivedmaterials herein have thermal degradation temperatures in air that areat least 30° C. higher than acrylate-functionalized glucose,acrylate-functionalized isosorbide, and polyester-basedsystems,^(38-39,42) providing a much larger temperature window forprocessing.

While the thermal parameters are important, adhesion performance iscritical in evaluating the potential of materials as PSAs. Herein, threetests were performed to assess adhesive properties: a 180° peel test(ASTM D3330, width 12.7 mm), a loop tack force test (ASTM D6195, width12.7 mm), and a shear strength test (ASTM D3654, contact area of 12.7mm×12.7 mm). The 180° peel test determines the force needed to tear astrip off the adherend at a constant speed; the loop tack force testmeasures the bonding strength that forms instantly between adhesive andadherend when they are brought into contact; and the shear strength testprobes the resistance of the adhesive to creep under an applied load. Inaddition to the above test, the mode of PSA failure qualitativelyevaluated as either adhesive (interfacial failure with no residue lefton the substrate) or cohesive (failure within the adhesive layer itself,leaving residue on the substrate), noting that adhesive failure is moredesirable for removable PSAs, while cohesive failure is more favorablefor permanent PSAs.^(28,39)

The neat P(4pSA-b-BA-b-4pSA) triblock bio-based copolymers exhibitedexcellent adhesion properties, without the addition of any tackifiers orother additives. 180° peel force and loop tack force data (stainlesssteel as the adherend) of P(4pSA-b-BA-b-4pSA) are summarized below inTable 2. Also, data for P(MMA-b-BA-b-MMA), Scotch® Magic™ Tape, andFisherbrand™ Labeling Tape are summarized for comparison. All foursamples had adhesive failure, leaving no residue on the adherend.

In the shear test, a 500 g weight was suspended from a SaBSa polymerstrip adhered to stainless steel plate, and the time for the SaBSa todetach from the adherend was recorded and summarized in Table 2. Threesamples of P(4pSA-b-BA-b-4pSA) were tested, with a range of failure timeof 570-810 min. The shear resistance of P(4pSA-b-BA-b-4pSA) was betterthan commercial duct tape, electrical tape, and Post-It® notes, but notas good as Scotch® Tape and Paper tape. The peel and loop tack forces ofbiomass-derived P(4pSA-b-BA-b-4pSA) also were as good as or better thanthose reported in potentially bio-based polyesters-based PSAs (with theaddition of tackifier) and acrylic PSAs with glucose or isosorbidecomponents (no addition of tackifier).^(38-39,42-44) These comparisonsreveal that lignocellulosic biomass-derived P(4pSA-b-BA-b-4pSA) polymersare extremely promising for PSA applications, without the addition oftackifiers or any other additives.

TABLE 2 Adhesion Tests Range shear test (Average) of Average (Time for180° peel force, loop track failure), N cm⁻¹ force, N cm⁻¹ minP(4pSA-b-BA-b- 2-4 (3.1) 2.2 570-810 4pSA) P(MMA-b-BA-b-MMA) 0.2-0.5unable to bind width the adherend Scotch ® Magic ™ Tape 1.7-2.0 1.4Fisherbrand ™ 3.5-5 3.9 Labeling Tape Commercial duct tape 200 (width 25mm) electrical tape (width 500 20 mm) Post-it ® notes (width <0.5 16 mm)Scotch ® Tape (width >10,000 20 mm Paper Tape (width 25 1400 mm)Testing MethodsCharacterization of Polymers.

The number-average molecular weight (M_(n)) and dispersity (Ð) of thesynthesized polymers and (P(MMA-b-BA-b-MMA) were obtained using aViscotek VE2001 size exclusion chromatography (SEC) instrument with THF(Optima) as the eluent (1.0 mL min⁻¹) and polystyrene standards(1.78-205 kg mol⁻¹) as the reference.

Glass transition temperatures (T_(g))s of all polymers were determinedusing a differential scanning calorimeter (DSC, Discovery Series, TAInstruments). The DSC was calibrated using an indium standard. Polymersample (2-5 mg) was loaded into an aluminum pan and hermetically sealedin air. A heating-cooling-heating cycle was carried out at a rate of 5°C. min⁻¹ under continuous N₂ flow (50 mL min⁻¹). ForP(4pSA-b-BA-b-4pSA)), the sample was first heated from 35° C. to 120°C., held at 120° C. for 2 min, cooled down to −90° C., held at −90° C.for 2 min, and ramped to 120° C. The procedure for P(MMA-b-BA-b-MMA,Kurarity LA2140e, Kuraray Co. Ltd.) was the same except that theexperimental temperature window was −90° C. to 150° C. The T_(g) wasdetermined as the midpoint of the inflection in the second heating.

The thermal degradation behavior of P(4pSA-b-BA-b-4pSA)) wascharacterized using thermogravimetric analysis (TGA, Discovery Series,TA Instruments). 9-11 mg of P(4pSA-b-BA-b-4pSA)) triblock bio-basedcopolymer was loaded into a 100 μL platinum pan and heated undercontinuous airflow (50 mL min⁻¹ sample purge, 20 mL min⁻¹ balancepurge). The sample was heated at 20° C. min⁻¹ to 110° C., annealed at110° C. for 15 min to remove possible residual water, cooled at 10° C.min⁻¹ to 50° C., held at 50° C. for 1 min, and heated at 10° C. min⁻¹ to600° C.

Tensile testing on lignin-based polymers was performed usingdog-bone-shaped testing bars (following ASTM D638, bar type 5, 5.3 mmgauge width, 0.8 mm thickness) that were prepared by compression moldinginto a Teflon PTFE sheet (McMaster Carr) on a PHI Hotpress at 200° C.,with an applied load of 9000 lb. Tensile testing was performed with aRSA-G2 Solids Analyzer (TA Instruments) in tension mode. The lower gripwas stationary, and the upper grip was raised at a speed of 10 mm min⁻¹to obtain tensile strength and elongation at break ofP(4pSA-b-BA-b-4pSA)) at room temperature. The measurement was repeatedwith four test specimens. Tensile testing on P(MMA-b-BA-b-MMA) also wasperformed for comparison, except that the testing specimens wereprepared with an aluminum mold, and the pressing temperature was 220° C.

The micro-phase separation characteristics of P(4pSA-b-BA-b-4pSA)) andP(MMA-b-BA-b-MMA) were probed by small-angle X-ray scattering (SAXS)(Rigaku SAXS instrument at the University of Delaware). The wavelengthof the beam was 0.154 nm, and the sample to detector distance was 2 m.The 2D scattering patterns were azimuthally integrated to a 1D profileof intensity [I(q)] vs. scattering vector q, q=4n sin(e/2)/λ (θ is thescattering angle, λ is the wavelength).

Testing Methods for Adhesive Compositions

Adhesion Testing.

Polymer films were prepared by casting polymer solution onto a 50 μmthick sheet of PET (McMaster Carr). 30 wt % P(4pSA-b-BA-b-4pSA)) or(P(MMA-b-BA-b-MMA) solution was made by dissolving 100 mgP(4pSA-b-BA-b-4pSA)) or (P(MMA-b-BA-b-MMA) into 230 mg o-xylene (SigmaAldrich, 97%). Polymer films with ˜20 μm thickness were prepared bycasting the solution onto PET sheet using a homebuilt flow coater⁴⁵ at aspeed of 10 mm s⁻¹ with a blade width of 12.7 mm and a gap height of 100μm. The films were dried under ambient conditions for 24 h beforeadhesion testing. Mirror-like stainless-steel plate (McMaster Carr) wasused as the adhered.

180° Peel Test in Accordance with ASTM D3330:

A P(4pSA-b-BA-b-4pSA)) film strip (width 12.7 mm) was adhered to thestainless-steel plate using a 4.5 lb hand roller. The stripes weremounted to a RSA-G2 Solids Analyzer and tested at a peel rate of 5 mm/s.The peel force was averaged across the plateau in force for foursamples.

Loop Tack Test in Accordance with ASTM D6195:

A P(4pSA-b-BA-b-4pSA)) film strip (width 12.7 mm) was formed into ateardrop-shaped loop and mounted to the upper grip of the RSA-G2 SolidsAnalyzer. The loop then was lowered onto the stainless-steel platemounted to the lower grip. The contact length of the strip was ˜30 mm.The upper grip was raised at a speed of 5 mm s⁻¹ until the stripdetached from the adherend. The maximum force was recorded as the tackforce, and the average of three samples was reported.

Shear Test in Accordance with ASTM D3654:

The film strip was adhered to a stainless-steel plate with a contactarea of 12.7 mm×12.7 mm, using a 4.5 lb hand roller. A 500 g weight thenwas suspended from the strip, and the average time to failure of threesamples was reported.

Copolymers Suitable for Use as Binders and Electrolytes

Synthesis and Characterization of Lignin-Based Monomer: GuaiacylMethacrylate (GMA)

Guaiacol used in the present example was purchased from Acros, butaccording to various embodiments of the present invention, guaiacolcould be sourced from biomass such as lignocellulosic biomass, asdescribed hereinabove.

Guaiacyl methacrylate (GMA) synthesis was adapted from previouslyreported method by Wang, as disclosed hereinabove, and from thedisclosure of the following article, incorporated herein in itsentirety: Gargallo, L.; Hamidi, N.; Radic, D., Synthesis, SolutionProperties and Chain Flexibility of Poly(2,6-DimethylphenylMethacrylate). Polymer 1990, 31 (5), 924-927 (hereinafter “Gargallo”).

Guaiacol (Acros, 99+%, 1 mol) and triethylamine (Fisher Scientific, 99%,1.2 mol) were dissolved in dichloromethane (Fisher Scientific) in around-bottom flask and placed into an ice bath. The mixture was spargedwith argon for 30 minutes before a solution of methacryloyl chloride(1.2 mol, Alfa Aesar, 97%) in DCM was added dropwise, and the mixturewas allowed to react overnight. The product was washed with saturatedsodium bicarbonate, 1.0 M NaOH, 1.0 M HCl, saturated NaCl, and deionizedwater; the solvent subsequently was removed by rotary evaporation. Themonomer was further purified by flash chromatography with silica gelwith ethyl acetate/hexanes mixtures and dried by rotary evaporation andon a vacuum line.

Synthesis of Lignin-Based Polymers: Poly(Guaiacyl Methacrylate) (P(GMA)or PGM)

Poly(guaiacyl methacrylate) was synthesized via activators regeneratedby electron transfer (ARGET) ATRP. GMA (1 mol), CuBr₂ (7.48×10⁻⁴ mol,Aldrich, 99.999%), N,N,N′,N″,N″-Pentamethyldiethylenetriamine (PMDETA,7.48×10⁻³ mol, Aldrich, 99%), tin(II) 2-ethylhexanoate (7.48×10⁻³ mol,Aldrich, 92.5%), and anisole (3.2 mol, Sigma-Aldrich, anhydrous, 99.7%)were added to a round-bottom flask and sparged with argon for 30minutes. The reaction mixture was heated to 60° C., and degassed ethylα-bromoisobutyrate (EBiB, 7.48×10⁻³ mol, Aldrich, 98%) was added to thereaction mixture to initiate the polymerization. The reaction wastracked via ¹H NMR spectroscopy and GPC in THF (>99%, optima, FisherScientific) of aliquots taken at 15, 30, and 60 minutes and was stoppedat 90 minutes. Aliquots and final reaction mixture were precipitated inmethanol to stop the reaction. The final polymer's GPC trace is shown inFIG. 8 . Because only a single peak was observed in the GPC trace, itwas determined that the ARGET ATRP was successful at controlling thispolymerization with good molecular weight control and low dispersity.

Synthesis of Lignin-Based Diblock Copolymer: Poly(GuaiacylMethacrylate)-b-Poly(Oligo-Oxyethylene Methacrylate) (P(GMA)-b-P(OEM) orPGM-b-POEM)

oligo-oxyethylene methacrylate monomer (OEM, >99%, stabilized,Sigma-Aldrich, average molar mass=500 g mol⁻¹) was purified by passagethrough a basic alumina column.

The as-synthesized P(GMA) was used as a macroinitiator for the chainextension with OEM via ARGET ATRP. P(GMA) (0.5 g), OEM (2.10 g), CuBr₂(9.88×10⁻⁴ g), PMDETA (7.64×10⁻³ g), and anisole (4 mL) were sealed in around-bottom flask and sparged with argon for 30 minutes andsubsequently heated to 60° C. Degassed tin(II) 2-ethylhexanoate (0.0179g) was added to initiate the polymerization, and the reaction wasallowed to proceed for 2 hours. The product was precipitated into waterand dried for 48 h at room temperature and 48 hours at 120° C. beforebeing brought into an argon-filled glovebox. The final polymercomposition was determined by ¹H NMR to have an overall molecular weightof 39,900 gmol⁻¹ with 72 wt % POEM.

DSC (Discovery Series, TA Instruments) was used to determine the thermalproperties of the as-prepared block copolymer (P(GMA)-b-P(OEM)) orPGM-b-POEM. In particular, the DSC was calibrated using an indiumstandard. PGM-b-POEM was loaded into an aluminum pan inside anargon-filled glovebox and hermetically sealed. Three heating and coolingcycles were performed at a rate of 5° C./min under nitrogen flow with atemperature range of −80-150° C. There were not significant changesbetween the second and third heating cycles, and the third cycle isshown in FIG. 9 . The T_(g)s were determined as the midpoint of theinflection in the third heating. There were two distinct T_(g)scorresponding to the P(OEM) (−56.1° C.) and the P(GMA) (66.5° C.). TheT_(g) of the P(GMA) is lower than previously reported in the bulk P(GMA)because of the lower molecular weight in the synthesized blockcopolymer. One simple strategy to mitigate this lower T_(g), would be toincrease the molecular weight of the block copolymer.

Lithium Salt-Doping of the as-Prepared Block Copolymer (P(GMA)-b-P(OEM))

P(GMA)-b-P(OEM) and lithium triflate separately were dissolved in THF(degassed via 3 freeze-pump-thaw cycles) in an argon-filled glovebox.The desired amount of lithium triflate solution was added to the polymersolution such that the overall ratio of [EO]:[Li]=20:1. The solutionthen was dried under vacuum until all of the THF was removed; thesalt-doped polymer was stored in an argon-filled glovebox.

Alternating Current Impedance Spectroscopy to Measure Conductivity ofthe Lithium Doped P(GMA)-b-P(OEM)

The lithium triflate-doped PGM-b-POEM was hot-pressed into disks undervacuum in an argon-filled glovebox. With a homemade test cell on aLinkam HFS91 CAP stage, a Princeton Applied Research PARSTAT 2273frequency response analyzer was used to extract the ionic conductivityof the samples.

First, the electrolytes were pre-annealed for 2 hours at 120° C., thencooled to 30° C. at 30° C. min⁻¹ and held for 30 minutes. Impedancemeasurements were taken under dynamic vacuum on heating from 30° C. to150° C. and two measurements were taken at each temperature to ensureconsistency. The average of the two measurements are reported herein,but deviations were within the size of the data point. The AC frequencyrange was 0.1-1 MHz, and the voltage amplitude was 10 mV. The resistanceof the electrolyte was extracted from the high-frequency plateau in thereal impedance data, and the conductivity was calculated as the samplethickness divided by the product of the sample area and the resistance.The conductivity of the as prepared lithium doped P(GMA)-b-P(OEM) wasmeasured as a function of temperature as shown in FIG. 10 .

The conductivity was maximized at 2×10⁻⁴ S cm⁻⁴S cm⁻¹ at 150° C. Thedotted line was indicative of the fit to the Vogel-Fulcher-Tammann (VFT)equation (equation 1).

$\begin{matrix}{\sigma = {\sigma_{a}e^{- \frac{B}{T - T_{a}}}}} & (1)\end{matrix}$Comparison of the Bio-Based Electrolyte Material of the PresentInvention, (P(GMA)-b-P(OEM) or PGM-b-POEM) with a Similar Non-Bio-BasedAlternative (Polystyrene-b-P(OEM) or PS-b-POEM).

The bio-based electrolyte material of the present invention was comparedwith a similar non-bio-based alternatives (PS-b-POEM). PS-b-POEM wassynthesized by ATRP. The polystyrene block was polymerized at 90° C. ina mixture of Cu(I)Br, PMDETA, styrene, and anisole, using EBiB as aninitiator. Reaction proceeded for 14 h and was terminated by coolingwith liquid nitrogen and exposing to air. The polystyrene block waspurified with passage through a neutral alumina and precipitated twotimes into methanol. The polystyrene was used as a macroinitiator in anATRP polymerization of OEM in a mixture of Cu(I)Br, PMDETA, OEM, andanisole at 90° C. The reaction proceeded for 4 h and was terminated bycooling with liquid nitrogen and exposing to air. The final polymer waspassed through a neutral alumina column and precipitated into a mixtureof equal volumes of diethyl ether and petroleum ether. The PS-b-POEM wasdried at 120° C. for 48 h and stored in an argon-filled glovebox.Conductivities of the P(GMA)-b-POEM doped with lithium triflate at[EO]:[Li]=20:1 and of a PS-b-POEM doped with lithium triflate at[EO]:[Li]=16:1 are shown in FIG. 10 . It should be noted that thebio-based electrolyte material has a higher conductivity despite thehigher salt doping ratio.

The conductivities shown in FIG. 10 were fitted with VFT equation (1)and the VFT fitting parameters σ_(o) and B are summarized below in Table3. σ_(o) is indicative of the effective charge carrier concentration andB is an effective activation energy, which is related to the segmentalchain motion of the polymer. Thus, the higher conductivity is largelydue to the bio-based polymer's higher effective charge carrierconcentration (despite a lower lithium ion concentration), as theeffective activation energy (B) is higher for the bio-based electrolyte.

TABLE 3 VFT fitting parameters of the bio-based and traditionalelectrolytes σ_(o) (S cm⁻¹) B (K) P(GMA)-b-POEM 0.052  1310 PS-b-POEM0.0064 1130

Furthermore, it should be noted in FIG. 10 , that by shifting theoperating temperature from 90° C. (<T_(g,PS)) to 110° C.(<T_(g,P(GMA))), conductivity increases by almost 300%.

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What is claimed is:
 1. An article comprising an adhesive compositiondeposited on a substrate, wherein the adhesive composition comprises abio-based block copolymer comprising: (i) at least one bio-basedpolymeric block comprising, in polymerized form, at least onepolymerizable bio-based monomer having a structure corresponding toformula (II):

wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl, propylene, apropanoate salt, a propanoate ester, an acetate salt, or an acetateester, wherein R₂ is a substituent comprised of at least onepolymerizable functional group that is an ethylenically unsaturatedfunctional group added via functionalization of a phenolic hydroxy (—OH)group, wherein R₃ and R₄ are independently selected from hydrogen ormethoxy, wherein at least one of R₁, R₃ and R₄ is not hydrogen, andwherein the ethylenically unsaturated functional group has beenpolymerized in the at least one bio-based polymeric block; and (ii) aco-monomer-based polymeric block comprising, in polymerized form, atleast one co-monomer other than the at least one bio-based monomers,wherein the at least one co-monomer comprises a butyl [meth]acrylate,wherein the bio-based block copolymer is a linear block copolymer. 2.The article of claim 1, wherein the adhesive composition is a pressuresensitive adhesive composition.
 3. The article of claim 1 furthercomprising one or more additives selected from the group consisting ofplasticizers, viscosity modifiers, photoluminescent agent,anti-counterfeit and UV-reactive additives, dyes/pigments, anti staticmaterials, surfactants, and lubricants.
 4. The article of claim 1,wherein the substrate comprises a polymeric film, a paper label, a tapebacking, a graphic article, a plastic article, a metal article, a wounddressing, a protection film or tape, or a release liner.
 5. The articleof claim 1, wherein the at least one polymerizable functional groupinclude methacrylate, acrylate, maleinate, maleate, fumarate,acrylamide, methacrylamide, vinyl, allyl, vinyl ester, or vinyl amidegroups.
 6. The article of claim 1, wherein the at least onepolyrnerizable bio-based monomer comprises: (a) a phenol [meth]acrylateselected from the group consisting of cresol [meth]acrylate,4-ethylphenol [meth]acrylate, 4-propylphenol [meth]acrylate,4-hydroxybenzaldehyde [meth]acrylate, and 3-(4-hydroxyphenol)propanoate[meth]acrylate; (b) a monomethoxyphenol [meth]acrylate selected from thegroup consisting of guaiacol (monomethoxy-substituted phenol)[meth]acrylate, 4-ethylguaiacol [meth]acrylate, creosol [meth]acrylate,4-propylguaiacol [meth acrylate, vanillin [meth]acrylate, and methylhomovaniliate [meth]acrylate (methyl2-(4-hydroxy-3-methoxyphenyl)acetate [meth]acrylate); (c) adimethoxyphenol [meth]acrylate selected from the group consisting ofsyringol (dimethoxy-substituted phenol) [meth]acrylate,4-methvisvringyilmethiacrylate, 4-ethylsyringyl[meth]acrylate,4-n-propylsyringyl[meth]acrylate, 4-i-propylsyringyl[meth]acrylate,4-propylenesyringyl[meth]acrylate, 4-formylsyringyl[meth]acrylate,4-propanoatesyringyl[meth]acrylate salt,4-propanoatesyringyl[meth]acrylate ester,4-acetatesyringyl[meth]acrylate salt, and4-acetatesyringyl[meth]acrylate ester; or (d) combinations thereof. 7.The article of claim 1, wherein at least one of R₃, and R₄ is methoxy.8. The article of claim 1, wherein the adhesive composition does notinclude a tackifier.
 9. An article comprising an adhesive compositiondeposited on a substrate, wherein the adhesive composition comprises abio-based block copolymer comprising: (i) at least one bio-basedpolymeric block comprising, in polymerized form, at least onepolymerizable bio-based monomer having a structure corresponding toformula (II):

wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl, propylene,formyl, a propanoate salt, a propanoate ester, an acetate salt, or anacetate ester, wherein R₂ is a substituent comprised of at least onepolymerizable functional group that is an ethylenically unsaturatedfunctional group added via functionalization of a phenolic hydroxy (—OH)group, wherein R₃ and R₄ are independently selected from hydrogen ormethoxy, and wherein the ethylenically unsaturated functional group hasbeen polymerized in the at least one bio-based polymeric block; and (ii)a co-monomer-based polymeric block comprising, in polymerized form, atleast one co-monomer other than the at least one bio-based monomers,wherein the at least one co-monomer comprises an alkyl [meth]acrylate, adiene, or an olefin, wherein the alkyl group is selected from the groupconsisting of methyl, ethyl, propyl and butyl, and wherein the bio-basedblock copolymer is a bio-based triblock copolymer, having a midblock andtwo glassy end blocks, wherein the midblock is comprised of the alkyl[meth]acrylate in polymerized form and one or both of the glassy endblocks is or are comprised of the at least one bio-based monomer inpolymerized form.
 10. The article of claim 9, wherein R₁ is propyl andR₃ and R₄ are methoxy; and wherein the triblock bio-based copolymer ispoly(4-propylsyringyl acrylate-b-butyl acrylate-b-4-propylsyringylacrylate) having the following structure (V):

and wherein n is in the range of 20-100; and m is in the range of50-1000.
 11. The article of claim 9, wherein the adhesive composition isa pressure sensitive adhesive composition.
 12. The article of claim 9further comprising one or more additives selected from the groupconsisting of plasticizers, viscosity modifiers, photoluminescent agent,anti-counterfeit and UV-reactive additives, dyes/pigments, anti-staticmaterials, surfactants, and lubricants.
 13. The article of claim 9,wherein the substrate comprises a polymeric film, a paper label, a tapebacking, a graphic article, a plastic article, a metal article, a wounddressing, a protection film or tape, or a release liner.
 14. The articleof claim 9, wherein the at least one polymerizable functional groupinclude methacrylate, acrylate, maleinate, maleate, fumarate,acrylamide, methacrylamide, vinyl, allyl, vinyl ester, or vinyl amidegroups.
 15. The article of claim 9, wherein the at least onepolymerizable bio-based monomer comprises: a phenol [meth]acrylateselected from the group consisting of cresol [meth]acrylate,4-ethylphenol [meth]acrylate, 4-propylphenol [meth]acrylate,4-hydroxybenzaldehyde [meth]acrylate, and 3-(4-hydroxyphenol)propanoate[meth]acrylate; (ii) a monomethoxyphenol [meth]acrylate selected fromthe group consisting of guaiacol (monomethoxy-substituted phenol)[meth]acrylate, 4-ethylguaiacol [meth]acrylate, creosol [meth]acrylate,4-propylguaiacol [meth]acrylate, vanillin [meth]acrylate, and methylhornovanillate [meth]acrylate (methyl2-(4-hydroxy-3-methoxyphenyl)acetate [meth]acrylate); (iii)adimethoxyphenol [meth]acrylate selected from the group consisting ofsyringol (dimethoxy-substituted phenol) [meth]acrylate,4-methylsyringyl[meth]acrylate, 4-ethylsyringyl[meth]acrylate,4-n-propylsyringyl[meth]acrylate, propylsyringyl[meth]acrylate,4-propylenesyringyl[meth]acrylate, 4-formylsyringy[meth]acrylate,4-propanoatesyringyl[meth]acrylate salt,4-propanoatesyringyl[meth]acrylate ester,4-acetatesyringyl[meth]acrylate salt, and4-acetatesyringyl[meth]acrylate ester; or (iv)combinations thereof. 16.The article of claim 9, wherein at least one of R and R₄ is methoxy. 17.The article of claim 9, wherein the adhesive composition does notinclude a tackifier.
 18. The article of claim 9, wherein at least onebio-based polymeric block comprises a bio-based copolymer block of4-propylsyringol [meth]acrylate and 4-propylguaiacol [meth]acrylate. 19.An article comprising an adhesive composition deposited on a substrate,wherein the adhesive composition comprises a bio-based block copolymercomprising: (i) at least one bio-based polymeric block comprising, inpolymerized form, at least one polymerizable bio-based monomer having astructure corresponding to formula (II);

wherein R₁ is hydrogen, methyl, ethyl, n-propyl, i-propyl, propylene, apropanoate salt, a propanoate ester, an acetate salt, or an acetateester, wherein R₂ is a substituent comprised of at least onepolymerizable functional group that is an ethylenically unsaturatedfunctional group added via functionalization of a phenolic hydroxy (—OH)group, wherein R₃ and R₄ are independently selected from hydrogen ormethoxy, wherein at least one of R₁, R₃ and R₄ is not hydrogen, andwherein the ethylenically unsaturated functional group has beenpolymerized in the at least one bio-based polymeric block; and (ii) aco-monomer-based polymeric block comprising, in polymerized form, atleast one co-monomer other than the at least one bio-based monomers,wherein the at least one co-monomer comprises a butyl [meth]acrylate,wherein at least one bio-based polymeric block comprises a bio-basedcopolymer block of 4-propylsyringol [meth]acrylate and 4-propylguaiacol[meth]acrylate.